The blue top ones are for Marine use... pretty much they carry alot of amperage to push the 12v (best I understand). They shouldn't be used in an automotive setting unless you are very familiar with electrical systems and understand the difference. (Don't ask me, I'm pretty clueless )
For us a Red top or Yellow top would be great...red for regular use and yellow if you have alot of extra stereo/electronic draws on your system.
I am wanting to actually look into one of these to save weight, space, and get the dry cell saftey and performance.