There's a whole thread for Gen 5 batteries and it seems the Odyssey Group 24 is the recommended one - there's a lot of discussion there about alternate battery sizes.
Has anyone replaced the OEM lame battery with a better one? Was doing some work on our 3.6 and after 2 hours with the dome lights on (yes, my fault for not shutting off) a dead battery quickly ensued. While charging I saw it had all of 490 CCA, which to me says it may be weak and underpowered...