I've only used the tenergy in sub c (4200mah) and they were not worth anywhere near what iI paid for them. They sems to be real hit or miss- some say the 3500s are great.
These guys won the AA shoot out that some digi cam folks held, PowerX. I bought several sets of four 6 years ago and used them in my Nikon until the battery door latch failed. They've had 100's of charges and do show some age. They were orig rated at 2300 and all 4 sets now take 1300+mah. I'm still using them. They've more than paid for themselves. Here's the shootout -
http://www.imaging-resource.com/ACCS/BATTS/BATTS.HTM
and here's PowerX -
http://thomas-distributing.com/index.htm Def not the only kind of batt they sell!!
I bought a set of 4 of their new 2700 and think they are overrated - mine take 2550 and a little but not close to 2700. I still think they're the tops in AAs. Expensive, but you tend to get what you pay for in batts.