new battery

I'll probably be getting a new battery this week for my Duster. I have been having issues where at random it will not start and needs a jump. The current one is just over three years old and its an exide. Can't remember the cranking amps. I was going to get something else other than an exide. Whats a good brand? I have heard many good things about optima but I can't spend $180 for a battery. whats a cheaper alternative? What cranking amps should I get? The engine is a mild 318, do cranking amps even matter? Oreillys has the superstart line, anyone have experience with these?

http://www.oreillyauto.com/site/c/d...vi=1232064&keyword=battery&pt=03321&ppt=C0005

Any help is greatly appreciated, thanks.