Originally Posted by Corkonian
I doubt, that there is a lot of difference with the lifespan. If possible, I would rather go for a deep cycle battery, but those aren't made for the vibrations occurring with automotive.
Perhaps you're right in the mild climate in which you reside.
Deep cycles will still be damaged by the lower charge voltage of the Honda system. Continual storage/operation at < near 100% SoC damage all Pb-acid based batteries.
Here in 45°C Phoenix, with 4 months annually of > 38°C days, batteries die quick deaths. It's rare you get a flooded cell battery to last more than 2-3 years unless the owner is diligent about maintenance of "maintenance free" batteries.
Pb batteries die via continual capacity loss due to cycling, heat damage and sulfidation.
When one starts with 40% more capacity, it takes longer for it to reach the threshold where capacity is too low to reliably operate the vehicle.
I have personally replaced the 151R in 2X HCH2 with 51R that were $10 cheaper. I am still in touch with the owner of one of the vehicles, and he's going on 5 years on the same cheap Walmart battery.
While based on a limited sample size, my experience in an extreme environment with 151R vs. 51R batteries in a 1.3L Honda Hybrid has shown that the 51R represents a greater VALUE due to its longer life and lower cost.