Replaced original 12 volt house batteries last Spring with two 6 volt Trojan T-105s hooked up in series. Worked pretty well. This Summer we are going on an extended trip, mostly boondocking and for safety's sake, I think that I will add 2 more T-105s; the two pairs in parallel with each other. Each battery weighs 62 pounds and it's a little extra weight. A friend's suggestion is to get a Trojan 12 volt scs225 and run that parallel to the two 6 volt in series. It would take 60 pounds off the weight. I have a class A with no real weight problems but I do like to stay as lean as possible. How do you all think?