As said before, unless you are upgrading your servos with something faster and better response rate over the Stds, then you will be greatly disappointed with the response of the aircraft on 4.8V. I have recently starting to switch over to the NiMH batt. packs, and haven't looked back. The NiMH 6V packs weight less than the 4.8V NiCads. If you are also looking to loose some weight, I'd strongly suggest going to the NiMHs.
Kevin