I recently decided to take a “crossover” rebreather course for the KISS Orca Spirit LTE rebreather (https://www.kissrebreathers.com/spirit-lte.html) with Drew McArthur at DiveTech in Grand Cayman (https://www.divetech.com/).
If you are in Grand Cayman, I definitely recommend you dive with DiveTech whether you are doing fun, recreational diving or serious 300+’ wall dives. Drew was an excellent instructor and the whole team goes the extra mile.
My “regular” rebreather is a rEvo Micro III FT (http://www.revo-rebreathers.com/products/revo-iii-closed-circuit-rebreather/micro-ft/) but I’m always open to trying new things. I had noticed all the KISS rebreathers at the 2019 Innerspace event and figured I should try one.
The number one question I got both during and after the course was “do you like it better than the rEvo?” I find myself repeating the answer over and over so I thought I would put it somewhere I could refer to people. 🙂
The bottom line is that “it depends.” I believe in using the right tool for the job.
The KISS is a very light, very straight-forward rebreather which means that it well suited for warm water and that it also has fewer points of failure. If you are a highly experienced rebreather diver, you can order a unit with no ADV, no OPV, etc. and have a very functional, very capable rebreather with almost no moving parts and very few things that can fail or go wrong. That is very appealing in a rebreather.
The “trim” on the KISS is amazing (as you can see in the picture above – but I should have had my bailout configured a little tighter). I had “acceptable” trim after just a few minutes with the unit. In my opinion, this is largely due to the placement of the counter lung (around the kidney area) and that there is one less tank valve and first stage “on your butt” (the unit doesn’t have an on-board diluent tank). It also has a great “work of breathing” characteristic when you are in trim.
One of the “negatives” (and also a positive in a sense) is that it doesn’t use a dedicated tank for diluent. Instead, your bailout tank is multi-purpose and used for wing inflation, diluent, and bailout. This means that, by default, your bailout gas is the same as your diluent. It isn’t a huge deal, but it does present certain limitations. It also means that you need to refill your bailout tank after dives and that you are “sharing” your diluent & bailout gas. You need to plan your bailout gas needs for that.
The rEvo (as I have it configured) is the opposite of the KISS. I have 5 oxygen cells that are connected to two different computers. My unit has an ADV, a OPV, a solenoid to automatically add oxygen to maintain a set point, temperature sticks to monitor on scrubber usage, etc. The upside is that I can have quite a few things fail and still stay on the rebreather during a dive. The downside is that it adds complexity and more points of failure.
My summary: use the right tool for the job and the KISS is a great rebreather.