Far greater? I taught many a Rescue Diver class, and they were mostly done with jacket style BCDs. I never saw any case where we floated a "victim" in which the victim was not floating face down. That is why the first step in the chief rescue scenario is to turn the victim over. If you are floating motionless with a BCD on, you will be on your face, no matter what style you have.
Really?? Have you tried it with a SP Stab jacket?