The are cheap, $10 for 4? I use exclusively Rayovac 2500 mah NiMH.
I have been using the same 4 batteries since October 2005. But it wasn't for a camera originally. I fly micro RC planes and use the NiMH batteries in the controller which is used to charge the lipo battery in the plane.
I can tell you, you recharge batteries far more often with micro RC planes than you do in a camera. I would get around 10 charges of the plane before I would have to recharge the AA NiMH in the controller. That could be charging daily back then.
I ran them in the RC controller until I bought my camera last Christmas. So, I have roughly a bit more than 2 years in the RC controller, and about 10 months in the camera. My camera is a Fuji S5700 which uses 4 of the AA NiMH. I can still leave the camera on all day long(8 hours), take shots all day (as long as I'm not using flash) and still have charge left in them for the following day.
Skip the Energizers, the Rayovac are definitely better batteries. RC fliers will know and understand batteries abit better than your typical photographer and we do tend to know which ones are the superior batteries.