My experience is similar to others. I use the grip, but for my own convenience, I only put batteries in the grip. I get about 800-1200 shots on a set of lithiums. These will last several shooting sessions for me, so I don't feel the need to load two sets of batteries in the camera.
I got tired of babysitting several sets of NiMH batteries after only a few months. I would only get 300-400 shots on a full charge. But if the cameras sat unused for a few days, the batteries would naturally discharge. It just wasn't worth the trouble. The NiMH batteries are now happily being cycled through a couple of radios and single-use Lithium Ions batteries power the D. By the way, you can by extra battery holders for the grip. I keep a loaded one in the camera bag. When your hands are full or you're in an awkward position, it's much more convenient to exchange the battery holder than fumble with individual batteries. See you later, gs
