Is it imperative to have AGM batteries with a solar set-up? Why? Could you not just use 2 6v batteries (not AGM's)? Do they last longer? How much and are they really worth the price difference?
You can use regular old 12 or 6 volt batteries no problem. AGM's are just better batteries. They charge faster and can supply more power faster. The latter being important when using a inverter for big draws. AGM's don't hardly off gas at all. They are more resistant to vibrations. If they are taken care of they should last longer. JMHO