Are you a kayaker Matt? Hey, that makes two of us. <img src="/images/graemlins/cool.gif" alt="" />

Agree with your comments. The wider issue here seems to be the expected use and environment of your kit. I wear a PFD most weekends seakayaking, but I don't need much cold protection from the elements so I use one of these, in the summer anyhow:

https://secure.worldwebms.com/www.glascraft.com.au/showitem.php?itemCatid=25

Not quite the same animal as the PFD developed by the Florida guy, but with sensible additions, does the job for warm water seakayaking. Minimum bulk, maximum breathability. So comfortable and light you don't know its there. So you wear it. A more bulky backup PFD stays at home. I always carry a small knife [folder], personal EPIRB, and whistle on lanyards around my neck. I have added an ACR 360deg. white light as a permanent fixture to the inflatable PFD.
The downside of the inflatables are cost, and maintenance. Mine goes back to the manufacturer annually, as recommended, for factory check.
On trips I add yet more kit to my person: a rolled up 25ft floating strip for air rescue, small parachute flare, and smoke. Stuff that people tend to forget in survival situations: heavy suncream and lipcream are always in my PFD pocket. Again, a reflection [ excuse the pun ] of my extreme environment.
But this is still less bulky than the Florida rig, which I would say may be OK for certain inshore and inland power boating applications.
But if I was going offshore on there's no way I would rely on a PFD without a fully sorted out harness. All you have to do is look at the experiences of those who have survived being washed overboard through proper harnesses.