.... from the picture it doesn't even look as though it would
float an unconscious person face-up.

From the picture, they don't appear to be inflated.

Maybe they're just pictures!
Which of course are perfectly suitable for rescuing people involved in
pictures of a ditching
In Canada, where I live, we are not allowed to use boating life
preservers in aircraft that are beyond gliding distance of land -
we have to use certified life preservers for aircraft - and they are
REALLY expensive - and they have to be self inflating, and have to be
sealed in an air positive bag - so if it is breached we know before we
need it - and we have to keep them current!

Tony
--

Tony Roberts
PP-ASEL
VFR OTT
Night
Cessna 172H C-GICE