The problem I think we're running into here is that the DIRmaniacs have taken the concept of the Air2 and compared it against the DIR configuration, which they claim is superior, and therefore its acceptable and reasonable to take cheap shots at the Air2.
But that's an improper comparison for a number of reasons, some of which I will list:
1. In an OPEN WATER environment, the "long hose" concept is a nice idea, but has some problems - particularly with hose routing using TRADITIONAL BCs.
2. Expecting everyone to toss their gear that they like and "DO IT RIGHT" is a great way to win converts. NOT! If your system won't adapt to various configurations, then you're asking for people to be all robots - and identical. That might work in a cave where there are very solid reasons for NEEDING the long hose (like being able to swim out single-file if you have to donate) but THAT argument simply doesn't apply to open water - at all.
3. Once you ACCEPT that people WILL use jacket BCs, back-inflate BCs, and even wings and plates, then you need to come up with a solution that works for what the person is diving.
With the exception of the plate + wing people, the long hose + necklaced secondary doesn't work very well, simply for want of routing capability.
Ok. That leaves us with a traditional Octo or an Air2.
The traditional Octo has problems. It is not usually where you can see it, especially with some vests that block vision forward and down. Since its not where you see it while swimming, if it comes loose you might not know it until after you fill it with sand, and the wrong time to figure it out is when someone needs to use it.
The Air2 has a significant advantage here in that it is NOT going to drag in the sand or mud. It is on the BC inflator hose, which is a LOT shorter and closer to the body. Its also in a KNOWN place all the time, since you are using it for buoyancy control on a frequent basis, and you know how to find that hose easily in a pinch.
The "might press the inflator buttons" argument is a red herring. I've TRIED to "accidentially" hit my inflator and do something underwater - if you don't pinch it off between something solid, the buttons won't activate. The return springs are simply too stiff. This SHOULD be the case for all inflators, I'd argue, but it definitely IS the case for the Air2.
The Air2 is very easy to breathe at depth. I've tested it at 100 fsw, and it breathed fine. Yeah, its stiffer than my S600 - but not by a lot, and try as I might I couldn't overbreathe it - and I DID try. If yours doesn't work well, perhaps it needs service.... like any other reg!
You want to argue that they are prone to leak? Gee, service again. What, that's a problem? How come its not for your necklaced backup? Oh, it is? Then what's the difference?
My Air2 doesn't leak AT ALL!
Me thinks the "loyal opposition" is proceeding from a false premise.
My premise is that the "default config" is a standard Octo. From that configuration, I argue that the Air2 provides a significant improvement in both safety and usability, while significantly reducing clutter.
Yours is parroting something I read on the WKPP/DIR web page in the form of a rant (almost word-for-word), and parroted as truth. That immediately calls into question whether you've actually ever owned - or used - one of these things.
