Tom, I'm glad you had chosen the military PUR Survivor 35 desalination, just don't exclude that, it's one of the most critical elements besides signaling and hypothermia. I've been stranded out at sea without an Epirb (made that mistake only once) and if it wasn't for a rescue tube and a dive alert, I wouldn't be here. Even with the rescue tube deployed it was the dive alert that got there attention to the tube. Floating around in the sea for a while is definably no fun and I had a strobe as well and was wondering what I was going to do if the batteries went dead. Now with todays locator's, there are quicker rescues and they may not need solar cells but I always keep them in the event as batteries fail. If you do go with AA batteries, use the Eneloop's, they have the longest storage time.

The reason I mention solar is I even have a 12.5 KW generator in the back with a 1.5 W solar charger from Harbor Freight for $8 and every year I go and check to see if it will crank and it fires right up. It keeps the battery topped off so I'm not screwed in a hurricane. I then incorporated 20 watt solar cells in my BOB and it powers every piece of electronics I use and all the batteries. And here's a video link that explains why solar is almost as valuable as food and water in todays military.
Ok, I'll stop my rant and raven about solar now, I just wanted you to think putting a small panel on board if you plan on using any electronics or batteries on board. And you would only need to do that if a rescue exceeded 48 hours, if not then it's not needed. But things happen....... Anyway my 2 bit's. I'll shut up now.

Video
http://www.globalsolar.com/index.php?opt...id=114recharges

http://www.powerfilmsolar.com/products/military/armytents/index.htm