X2, I buy my GC2 batteries from Samsclub as well, but I've done business with Batteries Plus and they offer great customer service. I get 7-8 years of reliable service and don't intend on paying more for certain brand names or lithium. Hurts to turn them in for core since they still have plenty of juice left in them, alas Samsclub has ridiculous pricing on GC2 couple times a year which tends to get me. For the price of gas I use on a single trip, I have reliable batteries that will last for at least 7 years. They are always being charged 24/7 by our Iota IQ4 when not on the road, keeps them healthy and happy while minimizing the need for topping off to once a year.