Just use decent ("decent" doesn't mean "ultra fast") charger even with average NiMH AA. Two sets of them is enough for a day for me. It's best for the cost and I could have extra pairs as well. (I have 4 sets and they cost me very little so I can have very long times of using gp2x)
Imho for general use NiMH are the best from every standpoint.
What a waste of money! For all you've spent on batteries you could have bought a 4 pack of rechargeables and a recharger and you'd be getting 3+ hours per charge!
That's NO waste of money. It tells everyone who DOESN'T want to get rechargables which disposables to stay away from and which to buy. Also, like BradN said, if you don't have your rechargables with you, you'll be able to get some good disposables to tide you over.
I have to disagree here... (not that I have much anything against disposable batteries but!)
The NIMHs can be recharged few hundreds times so you are getting many times more of your money worth with them. Using disposables with gp2x you are wasting money and resources. None is good and I can appreciate tests of disposables but they
aren't optimal way to power your gp2x.