I have found that the best optima batteries for automotive use with deep cycle capacities are blue top dual purpose . Not all of the blue tops are dual purpose. the reg. blues are just marine deep cycle not for starting. the yellows are deep cycle automotive aand the red are automotive starting . The blue dual are designed for smaler boats that don't have space for multiple batteries. they handle deep cycle and starting duties very well . I'm lucky if I have time to drive my Supra once a week and my dual has never let me down.
But I have to say that the best batteries out there are the stinger dry cells . I have one in my jeep mounted on its side for 3 years in the stock location 1700 cca's and 2 1/2 hours deep cycle reserve capacity with ultra low internal resistance so it charges easy than the stock battery. Only drawback was the price it retails for $349. but hey you get what you pay for.
But I have to say that the best batteries out there are the stinger dry cells . I have one in my jeep mounted on its side for 3 years in the stock location 1700 cca's and 2 1/2 hours deep cycle reserve capacity with ultra low internal resistance so it charges easy than the stock battery. Only drawback was the price it retails for $349. but hey you get what you pay for.