I have to replace my battery, and I am running about 1500rms+ in audio, I was told the OPTIMA batteries kick ass, I was even told to buy 2, a red cap for start up and a yellow top for the heavy load.

Any advise?

I've searched the forums the got nothing on this, just some scarce opinions here and there, but I need some real advise for actual users.

 

I am not sure if they make a battery in our size, but those batteries are awesome. I recently changed my battery on my 545i and compared all the different batteries around (duralast from sears, autozone batteries, bmw oem and actually walmart). I normally wouldn't buy parts for my car or even electronics from walmart (because I have heard that their are altered versions of the actual product), but their battery had the highest amount of cold cranking amps. Its been a few months and its been working just fine.