I'm a OWSI with about 800 + dives. I am cavern certified and looking and researching rebreathers to see if it makes sense and what are my best options. I have about 50 + side mount dives. I am looking for more bottom time and perhaps cave in the future. I was looking at KISS since there are a few instructors in ohio that teach it. I am also a Scubforce Dealer and looked at the SF2 but the price seems high even for a dealer and I have heard a lot of negative comments about it (head up, head down breathing). What are your thoughts?
Nobody has mentioned rEvo. I know some of the posters that have already chimed in will knock the rEvo, but I'll throw it out for your consideration anyway.
Disclaimer: I have completed through MOD3 training (full trimix - 100m cert) on the rEvo, but I don't have any real experience with anything else and I'm not an instructor on any CCRs.
Pros:
- lower profile than any other CCR, I think. If you're looking where you're going (i.e. head up), then it's even lower profile (overall diver profile, that is) than a Choptima, I think. I guess a side mount rig would be lower profile, top to bottom, but obviously wider.
- a rEvo Micro is light. The Micros are all titanium cases. Very easy to travel with. I pack mine in a suitcase with 2 dog beds for padding and it comes in just under 50#.
- requires minimal lead to dive with. I wear my trilam drysuit with my medium warm undies (for 50F water) and use no lead at all.
- build/maintenance/cleaning is super quick and easy. My checklists are about 1/5 the length of my buddy's that has a Tiburon.
- Can use up to 5 sensors. There ARE times when this can be an advantage. Other than the cost of sensors, I don't know of any downside to this.
- Minimal connection points to fail and let water in. Not that you can't flood one. I have done it. But, I think the design is more resistant to flooding than other units.
- Can rig the harness Hogarthian-style and have a VERY clean/uncluttered front/chest. I only have the 3-button MAV block on my front (well, and the Shearwater controller on my left arm and the loop with NERD) that makes it any different than diving single tank back mount OC.
- Scrubber design makes it EXTREMELY unlikely that you would ever have channeling or bypass for a CO2 hit.
- Scrubber design allows much more efficient use of sorb. I.e. you don't end up throwing away NEARLY as much good sorb as with other designs. Especially if you have and use rMS.
- rEvo rMS (rEvo Monitoring System) monitors your sorb usage in real-time and lets you know how much longer you have until you need to cycle out the top scrubber basket or both scrubber baskets. The early days (over 10 years ago) of rMS were marred by rMS components that crapped out fairly easily. From what I can tell, the designs have been updated and the current rMS probes and electronics are solid.
- With the rEvo DiveCAN controller, you can have rMS and 3 O2 sensors. Then, with a NERD or rEvo Dream (which includes HUD), you can have 2 additional O2 sensors. These 2 subsystems can be COMPLETELY independent - no physical connection between the controller and its sensors and the monitor and its sensors. And the monitor subsystem (i.e. NERD or Dream) is completely analog inside the unit. No electronics at all, inside the unit, for the monitor system to depend on. Only the battery in the NERD (or Dream).
- The rEvo has a Constant Mass Flow orifice. It flows O2 in the loop at a constant rate, no matter your depth*. You tune the O2 reg Intermediate Pressure to match your metabolism and it gives you a MUCH larger margin of error (i.e. more time) on failures that would result in the loop going hypoxic. I can swim gently for several minutes before my pO2 drops 0.1 ATM. If I sit perfectly still and relax, my pO2 basically holds constant. If you run a low SP and fly it manually, this means you go much longer in between times of needing to inject O2. If you let the electronics have full rein of your pO2, then it means the solenoid fires a lot less often than units with no CMF or needle valve.
- The counter lungs are very well protected from damage. They are inside the metal box.
- The counter lungs on the Micro are pretty much the perfect size (for me). They are only barely bigger than what gives me optimal loop volume. So, if I screw up and let my loop get too full, it's not nearly as bad getting a full loop on other units that have much larger CLs. Also, if the Micro CLs are too small for you, rEvo has a very inexpensive kit of spacers that make the case a bit thicker, allowing the CLs to expand more and give you the same CL volume as the rEvo Mini - which should be MORE than enough for anyone.
- You can get the rEvo with or without a BOV. I have it, but I have not used it (in OC mode) at any serious depth. However, when I have tried it, it does seem to breathe reasonably well. rEvo claims that their BOV breathes better than their DSV (which is the Draeger) and they do (from what I understand) have an ANSTI machine, and have measured the WOB themselves.
- The 3-button MAV block is nice. Meg diver/instructor friends have looked at mine and said "I wish my Meg had a 3-button block like that."
- Has a factory stand option (with completely customizable height), which is very easy to take on/off for travel and provides nice rings for clipping stuff to.
- Dive-Tronix is the U.S. Shearwater repair facility. They are also a factory-authorized rEvo (and Meg) service facility. That means you have a one-stop shop for getting a rEvo fully serviced - the unit itself and its electronics. And Dive-Tronix does awesome work, has great prices, and super fast turnaround. And they are awesome people in general.
- Mares bought rEvo. Dive Gear Express is a Mares and rEvo parts dealer. That means that, generally, rEvo parts are very "available" in the U.S..
- I have purchased 2 used rEvo III units, with Shearwater controllers and rMS, in the last 3 years or so. The most I paid was $5K. I bought a Mini first, then got a good deal on a Micro and bought that (and sold the Mini) for the lighter weight (better to fly with).
- There are several rEvo instructors in FL now and at least one that is willing to come and do training at Lake Jocassee (in SC). Lake Jocassee offers any depth needed for anything from OW to Adv Trimix, you don't get blown out, you can get trimix fills there (but make sure to arrange in advance to ensure there is helium there) and the boat rides are cheap...
- I have found my units to be pretty straightforward to work on myself - even for things like replacing the battery box (which contains the brains of the unit), the O2 and solenoid boards, etc.. I think about the only thing I haven't done myself is replace a counter lung (which I would not even attempt - that is something I would absolutely send it off to have done, if needed). Fortunately, even my Mini, from 2009, did not need either CL replaced during its 10-year service.
- if you want a NERD, you can use a NERD with a Fischer cable attachment, or a NERD with the 4-pin wetmate connector. rEvo offers the appropriate cable that gets installed into the unit, connected to the O2 sensors, to support either type of NERD. I bought my NERD with a Fischer connection and then later had Dive-Tronix change my NERD over to the 4-pin cable (at my expense, of course).
[too long, continued in next post]