Answered in your other thread - yes, 1 amp is ok. You'll get better life from them if you charge them at 0.5a. If time isn't an issue, I charge mine at 0.5, considered a slow charg. When I've got to have them charged ASAP, I'll use 1.0a charge rate.

3a with NiMh AAs - you'll possibly cause them to vent! Thats way too high for a NiMh. You don't want temps when they peak over 135-140F at the most.