Are the 6V batteries $180 apiece or $180 for a pair? A pair of 6V 225 Ah batteries will form a single 12V 225 Ah battery. If the Exide batteries are truly deep cycle batteries, and not hybrid starting batteries, three of them at $300 would give more capacity than the pair of 6V batteries at $360, if they are indeed $180 each.
As I understand it, usually the best bang for the buck in true deep cycle batteries ends up being the golf cart batteries. $180 apiece sounds rather expensive for them, from what I have gathered; Costco usually has ones (not necessarily quite as good or powerful as the Trojans) for somewhere around half that price, and golf cart stores may have similar prices to Costco.
