Ditto on the recommendation for the Diehard Platinum, although I do kinda regret not having a gel-cell like the Optima. The wife's Axiom has a no-name brand battery in it, so when her's goes out I may trade batteries with her and pick up an Optima for the VX. You can't argue with the super-high CCAs on the Diehard though; we did trade batteries for the trip to Wisconsin last winter, and it started up her Axiom in -17 degree weather on our last day there.

Honestly I don't think you can go wrong either way.