Canon Compact Battery Pack CP-E2 for 550EX

[JVphotography]

I'm planning to purchase a Canon CP-E2 battery pack for my Canon 550ex. I normaly use Ni-Mh rechargable batteries. Can anyone tell me if Ni-Mh batteries will work well with the Canon CP-E2 battery pack?

Many thanks in advance!
JV Photography

[Lionheart]

I use the Quantum battery packs to keep up my 550's during wedding shoots and other social events. These are rechargeable lead-acid batteries about the size of Tom Clancy paperbacks. They typically charge the capacitor on the 550 to full in a fraction of a second. I do use Ni-mh batteries as well in the 550's because of their larger capacity versus alkalines, plus they seem to charge the capacitor faster as well. Their main drawback is a lack of warning before they die. With alkalines, you know the batteries are going because it takes longer and longer to recharge the capacitor. With the Nimhs, you simply get to a point where they won't charge up the flash at all.
Quantum packs aren't cheap, but they'll last you pretty close to a lifetime.