Terror,
I just finished a WH 28% Edge. It has two 2700 MAh Sanyo packs wired in parallel. They were formed with a Litco Alpha 4 charger and both are showing in excess of 2900Ma when cycled at a 500 Ma discharge current. The Alpha-4 seems to work well with the NiMH batteries.

However, they are high-internal-impedance cells, maybe too hight to be used as a single pack in a 28% machine. Sanyo makes a 1950 cell with MUCH lower internal impedance that would probably be more appropriate when used in a single-pack application. Using two packs in parallel reduces the effective internal impedance of each of the packs by one half. I wanted the safety of the redundancy of a two-pack system and the 2700s weigh the same as the 1950s.

BTW, I would NOT charge that 2700 pack at 500 Ma. Higher internal resistance requires lower charge rates. I think 500Ma charge rates will greatly shorten the life, and perhaps reliability, of the 2700. In short, I agree with Tom... get a pack more appropriate for the intended use.