I replaced my two 12v wet cell Georgetown house batteries with 2 sealed group 27 marine deep cycle batteries. The group 27 gives you a little more capacity. Marine deep cycle batteries are true deep cycle. They are frequently used to power electric trolling motors as well as house batteries for a boat. Using an electric trolling motor for a day's fishing really depletes a battery and starter batteries would not last. I have used agm's in my 43' trawler (it had three 8d's which are huge) when I first bought it. I personally don't think agm's are worth the much higher cost, so as they die off I am replacing them with wet cell or sealed. Two have been replaced so far, one left to go. Original equipment was two 8ds for starting the two diesel engines and one 8d for the house and one group 27 marine sealed deep cycle for the generator. The 8ds weigh over 80lbs each and are not fun to remove/replace. Especially since they are down in the bilge area behind the engines. Very little working room. Big boats and Class A MHs have a lot in common. They both are expensive to buy, expensive to operate and repair, and the first owner gets killed on depreciation.
