"As AGMs are "sealed" they should not be subjected to the "equalizing" conditions."
As Maine says, Lifeline is BUILT TO BE EQUALIZED. East Penn IS NOT. Saying all AGM batteries are the same, or should be treaeted the same, is like saying it's OK to drink the orange Windex because it looks just like Fanta and Nehi.
Could be they are different products under that pretty box, huh? For the price LifeLine charges, they can afford to build a stronger case that can take the strains of equalizing. Maybe it is better, maybe it is not, but it definitely is not the same product.