The Lifeline AGMs are going strong after 3 years. I don't know the size (model) or capacity, but believe it's 4~12V. The camper has 2~2800W inverters...almost 6kW at 120V. Last week, I had ea. battery in the bank tested for the first time since they were installed with no weak cells.
Master Tech RV Service in Elkhart had excellent prices for Lifelines. I wouldn't want to guess what shipping might be. I was at the shop when I saw the batteries.