I have an inflatable vest which I got from West Marine that is in a belt back. It is more out of the way that the SOS suspender especially as I use a chest pack. I have never pulled the cord so I hope it works and I wear it whenever I go out on the bar.
Way back when, when I first started fishing PI someone fell off the bar and drowned. The next week there were signs on the beach saying "Keep off the sandbar." I actually went out anyway and a coast guard boat came by and actually signalled us all to get off.
What makes this place especcally dangerous is that it changes so much every year and you need to relearn it it season. Since I mostly flyfish now I tend not to fish it during the high season although the last few times I have been out there I have seen more and more flyrodders competeing for space with everyone else.
Chris