As with most survival gear, you keep it layered. Some gear (PFD, signal mirror, whistle, et al) should always be on your person. The grab bag with additional gear should be within reach as you start getting wet and whichever life-raft you have should have its own supplies.

While on the West Marine site (following links from DR's website) I stumbled on the The West Advisor. Looks like good info there, probably based on experience and what folks are buying.

Dry Bags are good to have, but once you go over the side, opening the bag will probably result in everything getting wet, so the items inside still need to be individually bagged; and once the seal is broken, your buoyancy is gone too if all it relies on is the air it holds.

Two bags that DR reported on are the ACR Electronics bag and the LandfallNavigation Abandon Ship Dri Bag. I kinda like the idea of a purpose built bag for this application. The bag itself is buoyant -- to a point. The LandfallNavigation Abandon Ship Dri Bag is how I'd go simply because it's a good place to store gear underway and if it ever does go over the side, DR tested it:
Quote:
This was the only bag we tested that had enough buoyancy (when closed) to support a decent quantity of weight, its full displacement easily supported 100 lbs of dense materials. That such bags also keep their contents dry is another benefit.


I couldn't find the West Marine brand bag that DR liked.


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Okay, what’s your point??