I have gone to AGM construction batteries in everything .
If you Wikipedia AGM you will get a good overview of why they are better than conventional lead acid batteries .
I purchased Exide EDGE AGM batteries for $140 each at BiMart (Oregon )
they recharge faster.
they do not spill or corrode
they can be drawn down further than conventional .
For Very serious dry camping it is better to go to 2 golf cart GC2 batteries .
The 6 volt are not available from exide EDGE AGM construction .
For dry camping we hook up our 2 AGM batteries in our diesel pickup to the 2 RV batteries with a # 2 AWG jumper cable 12 feet long .
We do not run the truck engine to recharge the RV batts .
A drive in the pickup every 2nd day suffices .