I'm still running regular wet cell trolling motor batteries. Two AC Delco 27 deep cycle. Not sure how old, but at least 6-7. They are tired. Time for new. Unless there is something I'm missing, I will be getting 2 more normal, old school batteries. I was at Sam's yesterday and see Duracell 27 at $99. Duracell AGM at $199 with very, very similar specs. Why? Why are the 2x (or 3x) the price? What would I gain from them. Assuming my 15+ year old, trusty Dual-Pro charger would work.

Thanks