pianotuna..... I have four Duracell Ultra Batteries.
We generally dry camp only a couple of days at a time. I think 3-4 would be the most we would ever dry camp in one stretch. Generally we want to mix in the dry camping with FHU in between. Or at least electricity.
This past 3 month trip we dry camped mostly one or two nights at a time with one place in North Cascades being 3 nights. If it is a single night I only ran the generator in the morning to get the slides in and for about an hour. The 175 amp alternator would fully charge the batteries while we drove the next day. Over one night the batteries would still be above 12.
The batteries only got below 12 once on our first dry camping night. After that I kept it above 12 at all times. When we dry camp the only thing running most of the time is the fridge. We stay outside most of the time hiking and exploring until the sun goes down and then off to sleep. I do have a meter that tell me how many amps are being pulled and most of the time it is 2-5. It also tells me if the charger is bulk or absorb charging.