Originally Posted by chef2sail
Here is an interesting article I found
"I used DEKA gel cells in the past for comparisons, but West Marine recently brought out a private label 6V gel cell series that they claim will sustain over 1,000 "full discharges". Given that reputable brands never claimed more than 600 cycles in the past, the West Marine claim may be a bit dubious. Due to West Marine's return policy, I'll give them the benefit of the doubt. West Marine also released a set of private label AGMs. Unless I missing something, these are very expensive and have a much lower cycle life than the Lifeline competition manufactured by Concorde Batteries."
Trojan claims over 750 cycles for the T-105, more than any other battery they make and as much as 2 1/2 times as many cycles as any 12 volt battery they make except for 2 designed for floor scrubbers.
I am not sure how they tested but they do have the largest research facilities in the US and they did publish it.
Below is an interesting quote originally from Trojan comparing battery types.