I've been using Optima AGMs for years on everything. Tractors, truck, wife's car, and Especially on a boat. Never leaks toxic acid because it is sealed. I'm sure there are some others as good or better, but optima is the only battery we've had so far that will continually crank these old , diesel tractors in cold weather. Mine have performed well on the water also. They have made a believer out of me. I would recommend running at least 2 batteries. 1 for cranking motor only, and another for accessories. Unless you want to get broke down a long ways from the truck from a drained battery that's to weak to start outboard.