I'm sure u'll get several opinions on this subject, but, my preference is Exide Group 31. I just replaced my 3 year old ones. Because I let the water get below the plates on one of them. One was still good but never team a 3 year old with a new one, just asking for trouble. We have an Exide store here, but Acadamy sells them as well as some other stores. They were $260 and some change. Our Exide store also sell seconds for much less but just have to be there when they come in, don't last a day... If I had kept the water checked like I shud have, I'd still be getting 6+ hours of constant 1.5, 1.6 mph trolling. I was getting 7-8 when they were new..