The battery will not be in a boat with on board charger, i will be taking in and out of a very small boat that my kids use behind the house and all the time, so it will have to hold up to a lot of charges daily. They can run a couple of batteries dead in a days time. I got the wal-mart and they don't last long at all when the kids have the trolling motor on # 5 all the time. Just trying to find them the best battery so we don't have to charge it so often.
All AGM batteries must be slow charged. If you fast charge it (to go fishing in the morning) you will damage it. The main reason for AGM batteries, by a large margin, is quick charges. The biggest problem Optima had early on was lack of consumer education on charging.