dockmasterdave wrote:
if I have 2 6v batteries and 1 goes bad, I have nothing.if I have 2 12v batteries and 1 goes bad, I have less amp hours, but my rig will still operate..
Assuming you're not talking about death from abuse or old age, it's specious reasoning.
The same argument could be applied to any 12v battery. What if someone dry camps with one 12v battery? Do we advise him/her to carry a spare? 2-6v batteries in series are nothing more than a 12v battery in two pieces, and it's no more likely to catastrophically fail than a 12v battery.
Having one battery fail is possible, yes, but probable? Hardly, and certainly not something you should base your battery selection on.
Hours of reading here:12v or 6 Dec 20132- 12v or 6v June 201312v vs 6v batteries 201312v vs 6v batteries 2006More 12v vs 6 200612v vs 6v 2010Why 2 6? 2006 Anybody had one 6v fail?2010 maybe 12v is better 201012v vs 6v Feb 2010