I don't get that. It is true that lead has gone up substantially in price over the last couple of years. However I am required to exchange a core, which has in it as much lead as the battery I am buying. So the price of the commodity is a wash, and the excuse is B.S.
I have used Lifeline AGM batteries for a number of years. One set in the RV is now 6 years old and going strong. The 4D sized one in the camper I just replaced at 12 years old. The ones in the boat have only been used for 3 years, but they were purchased 3 years before that in order to build the trays so they are six years old. Still seem to have near new capacity. AGMs need to be properly charged or they will die early, but the do seem to last if cared for.