I used to swear by the Optimas years ago but I don't have anything good to say about them anymore really - I have had red tops and yellow tops. The 1st one I bought I later replaced and that one is coming up on it's 6th year and in that time I bought 3 other ones. All of those later purchases failed me - most lost their charge and the ability to hold a charge. The warranty isn't as good as it used to be either... that should tell you something.