I've yet to feel the need to use digital $ervo$. Bear in mind that there are a variety of hydrimax batteries, some from Panasonic, some from Sanyo. I've read comments about avoiding use of NiMH batteries in high current setups due to their higher internal resistance. If you will be using a high current setup, such as dubya described, it would be a good idea to test the voltage while under load.

You've got an Accucycle Elite, do some discharge tests at varying loads and see what happens. If the voltage drops too low, you've got your answer. When you're done, report the results here, it would be interesting to know.