Back to the original subject, two 6 volt vs. three 12 volt, I bought 3 Energizer Group 29 RV/Marine batteries at Sam's Club yesterday. I will be replacing 3 of the same that are about 3 years old. The batteries are rated at 125 amps, so that is a total of 375 amps. I have 605 watts of solar. We probably use 70 to 100 aH per day. I had planned on moving the chassis battery and installing four GC-2 six volt batteries. I took the easy way out, but may still move the chassis battery and add one more Group 29 from Sam's Club.
2003 Winnebago Adventurer 38G F53/ V10 505 watts of Solar
1999 Winnebago Brave 35C Handicap Equipped
1999 Jeep Cherokee & 1991 Jeep Wrangler Renegade