On our last Boobs Cruise, the child's blow up alligator swim ring is all that I wore during the second half of the cruise. Safety and fashion all rolled in to one!
Here is photographic evidence that there is ample flotation on the cruise. In this picture you can see the Emergency Flotation device securely fasted to the bow for urgent needs.....
I too can't swim the greatest either (salt, fresh, pool doesn't matter water type) and my ample floatation devices are no help lol. I stayed in the middle of the boat and had no problems or concerns. We had VERY rough waters too. I even got up on the front to attempt to dance and have fun with AIWC, and despite the boats attempts to knock me down I wasn't concerned. The boat is big, so no concerns and someone will catch you if you start to loose balance.
