Optimas suck man. Strait up. With heavy usage, they have about a 9 month shelf life, and then they're trash. They won't hold charge, their CCA numbers are way over rated. I'd only use one if I maybe needed one in something like a race car with occasional use.
If you must use a gel cell battery, get something like a marine deep cycle battery. You can pick up something like a Marathon for a heck of a lot cheaper than an optima, or you can get some higher dollar ones like the Mega Cranks.
If you don't need a gel cell (say, you're not mounting it upside down) then I'd just get a high CCA big truck battery. There's tons of different brands out there.
We went through about 10 Optima's on our fishing boat before we gave up. We tried the blue tops, red tops, and yellow tops. All failed within 8-10 month's of constant drain/recharge. Heck, the blue tops even failed when not used often and keep under a battery tender.
I told one of my good friends that is into competition car audio about the optima's and he wouldn't listen to me. He bought 2 of them, and both died within 4 month's under strain. He now uses some marine deep cycles and has not had a problem.
Fair warning
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