Parallel 12volt, more capacity then AH rating? 2.7 x's more!

Using 12 volt jars shines when an odd number of batteries fit the available space. That can give a genuine boost to the number of watt-hours.

If cheap large wattage inverters were not in use then six volt would almost always be the route to follow.

Each person must use what serves their camping style best.

For a power pole princess even a tiny utility battery would work.