Best AGM batteries

X100 for Lifeline.

My Lifeline story. . . Alter a few years I noticed corrosion around one or the posts of one of my four Lifeline batteries. Long story short, reported it to Lifeline who ended up replacing all four of my batteries.

Rolls is the sole manufacturer for batteries for the F22 the B2 and B21 aircraft the F15, the F18 aircraft. The Abrams tank I am not sure of. The Oshkosh Humbvee
Replacement had Concorde batteries.
Everything they make is MilSpec without the paper trail

+1 for Lifeline if you want AGM in deep cycle service.

Nothing against Li batteries, BUT (indeed large BUT) to do them properly, one has to add in the cost of a proper Li battery charger, make changes to wiring so the alternator does not damage them, be aware of their temperature range etc.

If an RV is set up for Li batteries from the factory, they make a lot more sense to me.

BTW, have used Lifeline batteries in our sailboats and motorhomes.

X2 on lithium.

So far I am happy with these:
VMax AGM 6V

Wanted Trojan AGM, but hard to find at a decent price delivered.

X2 on Lifeline

Lifeline.

If your wallet can handle it, consider Lithium. You'll lose a lot of weight.