I used to go with Optima batteries and had good luck for a while, but got one that died in a year or so and Optima gave me a bunch of static about replacing it. Moved to Odyssey batteries (Road King, 800cc ATV, tractor, Ford F350 (2 batteries), diesel VW). I like several things about the Odyssey - they operate in any orientation, no spill, no maintenance, sort of a hybrid deep cycle and starting battery, take a good, fast charge if they are depleted. They use absorbed glass mat technology IIRC. Heavy as F~~~; I just purchased one for my tractor and it's over 50 lbs. They used to ship free, but now I think they charge a $20 surcharge over 50 lbs.