It's a solid regulator, but the fact is is that there is data, and then there is experience with the regulator. Even if one has data to suggest that my current reg shouldn't be having problems, it still is. Just because there is data and many people talk about it being great, though it is, I wouldn't replace it if I wasn't having problems with it. Anyone who knows me knows this. I don't think that harder to breathe is the right word for it- the air seems to be "thinner". I was using it a few days ago and the better word for it is that I don't have to breathe any deeper, it's just when I breathe "normally" at depth I don't get as much air as I should. At shallower depths even down to 45 ft. it performs fine.
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I dive Lake DeGray very frequently- it performs well there? Deepest I've been there is 71ft and I felt like I was breathing air at altitude. And it was finger numbing, face stinging cold
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I had my MK25/A700 in Lake DeGray at 39F this year. YOu know it gets COLD bellow 70 Ft! Didnt have the first problem other than Im an air hog. I had a D400 octo too and it worked great.
I dive Lake DeGray very frequently- it performs well there? Deepest I've been there is 71ft and I felt like I was breathing air at altitude. And it was finger numbing, face stinging cold