ive seen more optima's as main batteries, but some people like to run the front bat the same as the rear bats.
pretty much which ever one you can get cheaper.
i think you would need a Kinetik 2000+ (maybe 1400 depending on the CCA)
just know that they are deep cycle batts, it will take longer for start-ups.
i like my Kinetik HC 600 cause of the size, if your going this route for a rear batt look into batterymart, they have a knock off, that is almost exactly the same for the fraction of the price.