I wear the auto inflatable suspended style religiously.  As soon as I get out of the truck to launch the boat it goes on.  I take it off as the last step to buttoning the boat up after loading it onto the trailer.  I don't notice it being on, and it works.  I had mine deploy once and it happens so fast you wouldn't believe it.
My father, now in his mid seventies, would never wear a PFD.  He was once a very strong swimmer, but I told him he was getting on and the water isn't getting any warmer around our parts.  So I bought him one of the Cabela's auto inflating suspended style PFDs.  He wears it without fail, and perhaps more iota toy, without complaint.  He fishes with me and my kids a lot and he is now setting a great example for his grandsons.
A good point was made earlier that they do not count as a PFD on your boat unless you are wearing it.  Further, they Re not certified for use by children.  I think the minimum age is 16, but it might be 14.
Franko
MILF (Man, I Love Fishing)