[bruce]

NiMH batteries have a different chemical makeup than the NiCd and are not really effected by memory lost. It is also not recommended to deep cycle the NiMH batteries as it could damage it. When you are charging the NiMH battery, always check that they do not overheat. Heat is a killer for these types of battery.

With a new battery, it is recommended to charge your battery at half their capacity. This is why it takes longer for the initial charges. After a few times, you can charge about 2X the capacity.

Since you don't have one of those smart chargers, I would agree with the 3.5 hours charge time. Just check the battery if it gets hot while it is charging. If it does, unplug it and let it cool before recharging.

Also, with NiMH batteries, it's best to recharge them just before you need to use them. Even if they have been charged but left unused, they have a high self-discharge rate.