I'm with Jace187, I like the lithium and will change over this coming summer. We boondock a lot in the summer. Currently, I run two group 27 12V AGM Duracells with 200 watts of solar capability. Sometimes we go three or four cloudy days with no generator time.
The problem is the weight of those bad boys - they easily go 70 pounds a piece. When I switched over from the single, cheapie dealer battery, don't laugh, but my practice was/is simple. I park, connect the second battery with jumper cables to the installed house battery, connect the solar to the jumpered battery and start camping. It was supposed to be a temporary method to test the setup before installing the second battery. But, like my brother says: nothing more permanent than a temporary solution...
Once I started reading about the benefits of lithium, I was sold. Yes, it's expensive but with 3000-5000 charge/discharge cycles they should last ten years or longer. The only drawback is they should be disconnected when in freezing temps. The problem is with charging them, not discharging them, in freezing temps.