I use 2900 mAh rechargeable AAs. They have a higher mAh rating than the play and charge or quick charge kit so they should hold a charge longer, if you have spares you can just swap them over and carry on gaming, and of course you can use them in any other devices that take AA batteries.
I use 2500mAh rechargeables, and i have some 2650's too, they all last for weeks/months at a time. I have extra sets so just swap them over as and when, i just didn't see the point in those official wire and play gizmo's. As i have wireless controllers there was no way i was going to buy something that meant having wires trawling across the room. Kind of defeats the object.
i use rechargeable batteries too, picked up a charger with a four rechargeable AA's for 20 dollars, since then ive picked up a few more 2packs here and there. its nice, i never HAVE to buy batteries and the wireless keyboard, Guitar hero guitar, xbox controller, and other random shit around the house are always cool. plus its good for the environment and all that.
Check out Sanyo Eneloops if you are thinking of rechargeable batteries.
They seem to hold a charge past a year compared to other rechargeable batteries and they can also be precharged so you can just swap in a new set when yours runs out.
On Amazon they're like 30 bucks for a charger, 8 AAs and 2 AAAs.
If you went the Microsoft route it would be a Play and Charge kit for 20 and 11 for a second battery if you have two controllers. I feel it's a bit overpriced for what Microsoft is offering and even on ebay the price is maybe a few bucks cheaper but the shipping and handling always kills it.
I've read a little on Eneloops and they do seem to be superior to normal rechargeables. However i bought all my batteries/chargers before i'd heard of them plus i tend not to have to store mine charged for too long (before next use). However if i was just out to buy a stack of batteries now i'd choose Eneloops.
IMO (and most other people I talk to) Varta rechargable batteries are by far the best. They cost about $15 for two but in the xbox controller they last for atleast 1 and a half month's at a time.
i am using a Mad Catz Power Solution for Xbox 360 you dont get
any instuctions all so you plug in pag and wait for it to charge about 5 to 6 hours from new and lasts 13 hours 600ah on battery for £7 from asda i dont mind lol .no wonder the ms on is £15 it tells you its charged