I'm having much better life with AGMs, and any of my cars that are not daily driven, are on a Battery Minder or Granite Digital Save a Battery, battery maintainer. So far, so good. AC Delco AGM (made by Varta) is four years old, and still exceeds its CCA rating. (945, rated at 900) The two Varta (oem) AGMs in my M550iX BMW are five years old and pass a load test, they are also on a Battery Minder when parked in my garage.
I have had East Penn manufactured flooded batteries simply not last (one was private label Ray o Vac, the other a Duracell), both failed in less than three years, on a daily driven BMW, with occasional battery tender use for top ups.