I like the wet cell j185c approach. Cost effective, and proven performance.
I was adding more Magnum components into the open battery bay, as part of a MS2800 PSW upgrade. Along with other components related to a solar panel install. So I went AGM for coach, and less gassing maintenance free CAT 8D for chassis. X's 4 Lifeline L16's gives 800AH in the same basic footprint.
Suggest you determine your daily AH needs while not hooked up in an RV park. Add some contingency, I added 25-35%, then pick house batteries that support your expected usage.
Many, many ways to go on this. One will be right for you.
Roo II is our 04 Country Coach Allure 40'
OnDRoad for The JRNY! Enjoy life...