Some of the previous answers are well informed while others are just plain dogmatic and reflect either a lack of knowledge, real world experience, or both.
- Using an Air 2 and/or a long hose requires you to dontate the primary. However this is no big deal as in the real world, OOA recreational divers will mug you for your primary at least 3/4 of the time. Consequently it;s a moot point whether you were trained to donate your primary or not. If you were not trained to donate your primary, you need to practice it as it will be what happens when you need to share air for real.
- Air 2's and their clones are very relaible and, if properly adjusted in the first place seldom if ever "come out of adjustment" or leak. They use a very simple, very reliable downstream poppet second stage design and are no more complex than an octo. If you had problems with them leaking, it's because your tech did not know what he/she was doing.
- Adding or dumping air while breathing off an Air 2 is not hard. Most BC's have a pull dump on the shoulder and tugging gently on the middle of the hose while the Air 2 is in your mouth is more than adequate to dump while vertical in the water. Even operating the buttons on the unit while breathing off it is not hard and contrary to one post, unless you are mentally challenged or have severe ADD, your hand going to the Air 2 now and then to add or dump air is not going to distract you orcompromise your safety.
- The Air 2 does breed familiarity and since you use it on every dive, your hand will know exactly where it is in an emergency. You cannot say the same for a cionventional octo.
- Also, since it is constantly used, it stays flushed and reasy for use. I see several octos each year that come in totally non functional filled with rocks or sand, with faulty exhaust valves or with holes in the diaphragm or mouthpiece. In an emergency what would have occurred with this neglected octo is that the diver would have lost his/her primary when he/she got mugged by the OOA diver. And then when the diver tired to access his/her own octo, they would have basically panicked and got in a struggle with the OOA diver for the only working air supply. In the rare cases where the OOA diver went for the octo, first, they would have panicked and mugged the diver for the primary when they discovered the non-functional or very wet breathing octo.
So in my opinion, when it comes to considering the primary use of an octo, an Air 2 will work every time in the real world, while a conventional octo will not due to neglect and positoning where it is frequently drug through sand, rocks, vegetation etc.
- Using an Air 2 is fine in a recreational situation. Head movement is somewhat limited, but if you are on the Air 2, you should be ascending anyway so it's a short term limitation by definition. And if used with a donated long hose, you have the ability to rotate your body away from the OOA diver slightly if you need to see something that way (whether you are breathing off an Air 2 or a regular octo). That is not an option however if you have donated a short hose.
- A long hose is great to share air with in ANY situation. If you feel the OOA diver is panicky you can still hold them close by the BC. But in my experience what breeds panic and maintains panic is the feeling they get that the short hose octo is not secure and is at risk of being pulled from their mouth. That never happens with a 5 to 7 ft hose. When breathing off a long hose the OOA diver has enoitgh hose tha tthe reg feels sescure and they have enoughh lenght to allow them to ascend normally without feeling cramped and can move and maneuver to manage their ascent without risking loss of the hose. It is not just for over head environments and the comments I have gotten from conventionally trained short hose octo divers who have shared air off my long hose in training or real workd situations is bascically "WOW..that's really great where can I get one?"
- Long hoses do not require extensive training to deploy. It is not rocket science. For example a 5' long hose used by a recreational diver will route under the right arm, up across the chest over the left shoulder around the back of the neck to your mouth. Deploying it requires giving the reg to the OOA diver and tilting your head forward slightly. The only thing really different is that it is oftena good idea to use a folding snorkel in your pocket to prevent the hose from hanging up on it during deployment. Worst case, if you don't visualize verbal descriptions well, you might need a 30 second demonstration of how to do it. If you are a diver and you cannot figure out how to deploy a long hose based solely on this description and/or a demonstration, you probably don't belong in the water.
- Getting out of the water and up the ladder with a long hose is much easier than doing it with a 30" hose if the OOA diver needs to have the reg in their mouth until they are firmly on and started up the ladder. (If fact I'd say doing it with a short hose is just about impossible.) Just keep the exiting diver on your right side and retrieve the hose when they spit out the reg half way up the ladder. Wrap it back around the back of your neck and then exit yourself. An unused long hose will bascially lay over your right shoulder and won't go anywhere. If you want to make doubly sure of this, clip the boltsnap to a D-ring somewhere in the right shoulder area.
- I am not a real big fan of the bungeed octo, but it does offer three advantages. 1) It tends to be in an area where it will not get drug in the sand, vegetation etc. 2) It tends to be very easy to locate and 3) It can usually be accessed without the use of hands. The first two are real advantages while I have, in 21 years of diving, never seen a recreational need for accessing the octo with out using your hands - it's just not all that important in recreational diving.
- On the downside: 1) The bugeed octo tends to have poor streamlining as the hose sticks out to the side due to the excess hose lenght flapping in the current when the octo is bungeed around your neck - I'd much rather run a short hosed second stage over my right shoulder and clip it to a d-ring on the right shoulder or on a centerline pocket mounted D-ring depending on hose lenght as it results in a more streamlined configuration. (The bolt snap is attached to the mouthpiece via an o-ring looped through the ring on the boltsnap and stretched over the mouthpiece - this allows the second stage to be pulled free in situations where you do not have time to undo the snap and it allows it t be restowed later if neccesary) 2) It can get interesting when a rec diver graps your bungeed octo even if the mouthpiece slips free easily. 3) It interferes with snorkel use on the surface.
- In short, using an Air 2 is fine, using a long hose is fine and using both together is fine, and I'd argue that using both together has some significant advantages for a recreational diver.
- Using an Air 2 and/or a long hose requires you to dontate the primary. However this is no big deal as in the real world, OOA recreational divers will mug you for your primary at least 3/4 of the time. Consequently it;s a moot point whether you were trained to donate your primary or not. If you were not trained to donate your primary, you need to practice it as it will be what happens when you need to share air for real.
- Air 2's and their clones are very relaible and, if properly adjusted in the first place seldom if ever "come out of adjustment" or leak. They use a very simple, very reliable downstream poppet second stage design and are no more complex than an octo. If you had problems with them leaking, it's because your tech did not know what he/she was doing.
- Adding or dumping air while breathing off an Air 2 is not hard. Most BC's have a pull dump on the shoulder and tugging gently on the middle of the hose while the Air 2 is in your mouth is more than adequate to dump while vertical in the water. Even operating the buttons on the unit while breathing off it is not hard and contrary to one post, unless you are mentally challenged or have severe ADD, your hand going to the Air 2 now and then to add or dump air is not going to distract you orcompromise your safety.
- The Air 2 does breed familiarity and since you use it on every dive, your hand will know exactly where it is in an emergency. You cannot say the same for a cionventional octo.
- Also, since it is constantly used, it stays flushed and reasy for use. I see several octos each year that come in totally non functional filled with rocks or sand, with faulty exhaust valves or with holes in the diaphragm or mouthpiece. In an emergency what would have occurred with this neglected octo is that the diver would have lost his/her primary when he/she got mugged by the OOA diver. And then when the diver tired to access his/her own octo, they would have basically panicked and got in a struggle with the OOA diver for the only working air supply. In the rare cases where the OOA diver went for the octo, first, they would have panicked and mugged the diver for the primary when they discovered the non-functional or very wet breathing octo.
So in my opinion, when it comes to considering the primary use of an octo, an Air 2 will work every time in the real world, while a conventional octo will not due to neglect and positoning where it is frequently drug through sand, rocks, vegetation etc.
- Using an Air 2 is fine in a recreational situation. Head movement is somewhat limited, but if you are on the Air 2, you should be ascending anyway so it's a short term limitation by definition. And if used with a donated long hose, you have the ability to rotate your body away from the OOA diver slightly if you need to see something that way (whether you are breathing off an Air 2 or a regular octo). That is not an option however if you have donated a short hose.
- A long hose is great to share air with in ANY situation. If you feel the OOA diver is panicky you can still hold them close by the BC. But in my experience what breeds panic and maintains panic is the feeling they get that the short hose octo is not secure and is at risk of being pulled from their mouth. That never happens with a 5 to 7 ft hose. When breathing off a long hose the OOA diver has enoitgh hose tha tthe reg feels sescure and they have enoughh lenght to allow them to ascend normally without feeling cramped and can move and maneuver to manage their ascent without risking loss of the hose. It is not just for over head environments and the comments I have gotten from conventionally trained short hose octo divers who have shared air off my long hose in training or real workd situations is bascically "WOW..that's really great where can I get one?"
- Long hoses do not require extensive training to deploy. It is not rocket science. For example a 5' long hose used by a recreational diver will route under the right arm, up across the chest over the left shoulder around the back of the neck to your mouth. Deploying it requires giving the reg to the OOA diver and tilting your head forward slightly. The only thing really different is that it is oftena good idea to use a folding snorkel in your pocket to prevent the hose from hanging up on it during deployment. Worst case, if you don't visualize verbal descriptions well, you might need a 30 second demonstration of how to do it. If you are a diver and you cannot figure out how to deploy a long hose based solely on this description and/or a demonstration, you probably don't belong in the water.
- Getting out of the water and up the ladder with a long hose is much easier than doing it with a 30" hose if the OOA diver needs to have the reg in their mouth until they are firmly on and started up the ladder. (If fact I'd say doing it with a short hose is just about impossible.) Just keep the exiting diver on your right side and retrieve the hose when they spit out the reg half way up the ladder. Wrap it back around the back of your neck and then exit yourself. An unused long hose will bascially lay over your right shoulder and won't go anywhere. If you want to make doubly sure of this, clip the boltsnap to a D-ring somewhere in the right shoulder area.
- I am not a real big fan of the bungeed octo, but it does offer three advantages. 1) It tends to be in an area where it will not get drug in the sand, vegetation etc. 2) It tends to be very easy to locate and 3) It can usually be accessed without the use of hands. The first two are real advantages while I have, in 21 years of diving, never seen a recreational need for accessing the octo with out using your hands - it's just not all that important in recreational diving.
- On the downside: 1) The bugeed octo tends to have poor streamlining as the hose sticks out to the side due to the excess hose lenght flapping in the current when the octo is bungeed around your neck - I'd much rather run a short hosed second stage over my right shoulder and clip it to a d-ring on the right shoulder or on a centerline pocket mounted D-ring depending on hose lenght as it results in a more streamlined configuration. (The bolt snap is attached to the mouthpiece via an o-ring looped through the ring on the boltsnap and stretched over the mouthpiece - this allows the second stage to be pulled free in situations where you do not have time to undo the snap and it allows it t be restowed later if neccesary) 2) It can get interesting when a rec diver graps your bungeed octo even if the mouthpiece slips free easily. 3) It interferes with snorkel use on the surface.
- In short, using an Air 2 is fine, using a long hose is fine and using both together is fine, and I'd argue that using both together has some significant advantages for a recreational diver.
