I have Exide EDGE AGM batteries .
They are made in North Carolina , I believe .
I got mine at BiMart for $ 140 each here in Oregon .
I first got group 78 for my Duramax , 2 batts .
EDGE only comes in one size of RV/Marine .
I got those for my TT .
Wikipedia AGM to discover the best reasons to go AGM .
For Heavy loads the 6 volt GC2 batteries are probably best .
EDGE AGM is not available as a 6 volt .
My research showed that these Edge AGM batts are not " finicky " about charging rates .
I also went to Exide EDGE AGM for the boat and as a replacement battery for our 7 year old Mercedes E350 4matic .
I had previously paid $ 200 for an Optima for our Porsche .
I think the EDGE AGM is a bargain for a USA made battery .
In the truck it comes with a 4 year 100% replacement guaranty .
2 years for the RV / Marine.
I am told I can expect 7 to 10 years useful life from these AGM if I do not deplete them below 40 % repeatedly .