Well I just pulled out the huge old mopar batteries out of my truck. Replaced them with some cheap optima reds ($110 each at costco).

They sure are smaller and alot lighter. Even off the shelf with no charge the truck fired up quicker than with the others (1.5 sec vs 2.5 sec maybe?)

I am curious though, if anyone has considered Optimas D31A battery?

The regular optima red's are only 90 min reserve, these boast a 155 min reserve. Pretty big in size too, but as of now these optimas have several inches on each side extra now.