I hear good things about Interstate, and that was my last purchase. Can't tell you how they hold up because they were just bought a few months ago. That said, I wouldn't get toooo caught up in branding as it seems Johnson Controls makes most of the them. In regards to battery size you could just look for what size fits in your current battery holder, then find the battery with the largest reserve capacity. Or get technical, contact the mfr to determine amp draw of your trolling motor, and determine what you really need.