Our 1981 truck camper (which I have much renovated) has its not- sealed battery box inside with no special outside venting. Problem came when I installed an LP alarm. My set of 6s in there, while on shore power Float (never mind actual charging) kept setting off the alarm. Cure was to put AGMs in there instead.
Otherwise, I would not get AGMs. Cost a bunch more per AH and can't use an hydrometer.
Only time I wished for them is camping in the winter when the batts outside get cold and lose AH capacity. Be nice to have the batts inside where it is heated and they don't lose their AH.
