Its all a matter of your specific use. It was mentioned that the inflatable PFDs would be no good if you were knocked unconscious and fell in the water. In such circumstances, only a Type I PDF would help you as it is the only one designed to turn over an unconscious user. These are what most people know as offshore PFDs and they are big and bulky. The problem is that most people simply are not going to wear something like this for moderate recreational use. Thus, most people do not wear one at all when it is a good idea to do so because they don't like the look or the bulk.

Enter the new low-profile, self-inflating and suspender-type PFDs. No doubt these are not as efficient or maybe even as reliable as a Type I or Type II PFD. But, people are more likely to wear them and the PFD you are wearing is 100 times better than the PFD sitting in the boat while you are treading water.

YMMV.