As long as you stick to a decent brand (energizer etc) id just use the energizer chargers. They take for ages, but if you have the time, its a much better way. plus they seem to charge the cells individually too. when on the go, i set my Integy charger to 8 cells, set the rest of the parameters, 1 amp, but cant remember what mv cutoff. My Helios uses a tonne of battery. Ive been pleased with it tho, racing up to 4 classes in the one day with it, i can easily last a day, and have gone 2 days straight before charging. I always have a backup set of batts ready to go anyhow.
also check out the amp number off a std charger like the energizer. from memory, they charge at like 130Ma so keeping around there is a good idea.
Aaron "AJ" Freind