I know this is a buoyancy conversation, but in terms of safety even CGA type III vests are not designed to turn an unconscious wearer.
“A TYPE III PFD, or FLOTATION AID, is good for calm, inland water, or where there is a good chance of quick rescue. This PFD type will not turn unconscious wearers to a face-up position. The wearer may have to tilt their head back to avoid turning face down.”
I’ve been through WSI training. CGA vests are required in MN on public water where we ski, but I choose to wear a comp vest (zipper plus 2 buckles) for early morning skiing with a trusted boat crew.