@Wibble made a point about rEvo flooding. He said its weakness is flood resistance. I want to correct that. It is very flood resistant. It is not flood tolerant. In other words, the design of the rEvo is such that it seems (in my VERY inexperienced view) to be very resistant to flooding. There are only 2 hoses in the breathing loop. With the standard DSV, there are only 2 nuts to put on and tighten. Other units typically have 4 hoses, T pieces, and, so, many more places where an O-ring could leak, for example. Some other units also have exposed counter lungs which, I *think*, are more likely to get a cut or rip in them during a dive than the rEvo counterlungs. It seems to me that the rEvo is probably one of, if not the most, flood RESISTANT units on the market.
What it is not is flood TOLERANT. Meaning, once you flood it, you are not getting the water out during the dive. Everyone talks about the rEvo like it's a 100% negative to the rEvo on anything related to flooding. But, to me, it seems like it's more of a pros and cons situation. It's less likely to flood (a pro), but you can't get the water out if it does (a con). Only you can decide which way to go on that.
I flooded my Micro once. Totally my fault during assembly and checks. It was a slow flood and I completed a 90 minute dive, on the loop the whole time. I didn't realize it was flooding. My only clue, until close to the end, was that it seemed a little harder to breathe than normal. But, even then, I wasn't sure. Towards the end, I rolled onto my side and the salt water got into the sensor tray and 3 of the sensors went whacky. But, the 2 that were only connected to my NERD continued to function perfectly and they, with the NERD and me flying the O2 manually, are what got me out safely.