AGM battery questions

Have had Yellowtop Optima's in three different rides and have never had acid buildup on any of them. My 1st one still in use has lasted over 11 years just in my possession and was already in a car I purchased.I had never kept it on a trickle charger but last year when it got weak I started keeping them all on the trickle. Before getting another new one last year I read all the reviews and folks were down on them stating they weren't made as good anymore but I bought one anyway so we shall see. They were a helluva lot cheaper then the Odyssey's.