If you run two batteries, you have to match them. Either gel or lead acid. They have different resistance to charging current and will not charge equally if they are different types. Personally, I run two Optimas, red and yellow, and have no trouble. I am not sure what would happen if you mix brands. You would have to get some stats from the manufacturers on charging resistance to answer that question. I also have an inverter, and they do suck the juice. Now one question, you aren't trying to run a 110 wire feed with one are you?