Napa's batteries are Deka, including their Napa Legend Premium line.
Sears DieHard Advanced Gold is also a Deka AGM. The DieHard Platinum is an Enersys/Odyssey AGM.
The AAP Autocraft Platinum is a JCI-made AGM. Not my first choice over the Deka options, but could be a good value if they don't make the other AGM's in your size, and AAP does have those online discounts, too.
Interstate batteries are very good, and I'm sure their AGM's are no exception. Also made by JCI.
I would avoid Exide since they're not as good. Pep Boys Bosch is Exide.
Originally Posted By: chefwong
Actually the BP X2 out here in the Northeast, are made by Northstar.
Wow that's surprising, since Deka batteries are made in the northeast! (East Penn batteries really are made in Eastern Pennsylvania!)