Your Community Leader is paisan.
I swapped to a AGM battery by Optima after about 40 months. That was about 40 months ago and still the Optima is doing fine. I went with the more expensive Optima spiral wound absorbed glass mat battery type to avoid the acid mess. No more rust and no more corroded battery terminals. The optimas also have very low internal resistance which gives something like 1000+ Cold Cranking Amps from a battery that is fairly light weight.
I use a deep cycle AGM in my boat from LifeLine a concord company brand for the AGM advantage plus more reserve amp hours than can be found in an optima.
Champion also makes a spiral wound AGM battery.
I'm not a fan of cartalk or Jiffylube but they provide some decent info on this subject...