Just to add to what Nick said, keep in mind float bags limit the amount of water that can gets inside which means there is less to get out. If you have ever had to re-enter and pump one out you will appreciate that.

I build SOF boats and they have no bulkheads. When practicing rescues, even with just an inch of water in the boat, there is a huge difference with and without bags in place. Pumping takes less time but the boat is more stable with less water in it too which makes re-entry easier.

Also keep in mind a proper fitting bag, slightly larger than that boat, will fill more space and means less water. A bag that is to small may float out if you don't have it constrained somehow.