Well I'd suggest you dump the NiMH chemistry batteries from Horizon and go with the Eneloop type NiMH cells available from most any of the recognized vendors like NoBS for your pack. I would toss the included charger for the 12X as it will only cook the batteries with it's higher than normal charge voltage.
While the Eneloops say you can safely charge them at a pretty high (to me it's high) rate for a NiMH battery I've never felt good about doing that so I have just a standard JR walwart and charge the batteries overnight. I don't use my 12X much anymore but I can go in there and turn it on right now and it'll have enough of a charge to use even though it's been months since it was charged. Great batteries for tx's those Eneloops...
