OOOH, OOOH, I got to use mine!!!
from my experience getting to "use" mine...
here's my take on bags.
The BCA & ABS seem like they would float you face down, Snowpulse seems like it would float you in the "whitewater float position" in comparison.
Face down seemed sketchy, but I didn't get any snow in my mouth after I was brought to the top & I was able to swim like I was in water.
BCA & ABS seems like they give you room to move your arms so that you can swim... which I guess I'm pretty strong in thinking is needed since it's exactly what saved me.
I like the solid trigger on the ABS it was easy to find & I got it on the first grab, and pulled it right through the velcro no problem.
The ABS trigger seems flimzy, but I saw a guy on BCR who found a way to make it stay in one place... BCA should read that thread, it's a huge improvement imo.
The strap on the snowpulse I've never pulled, but it seems like you could miss it as well.
That's my take based on my 6 seconds of "expert status"...
