How smart are we talking? SkyRC or similar, with a display?
NiMH is a bit of an issue for chargers. With lithium (or lead) batteries, you can tell a charger what voltage the battery is, and it will know what voltage to limit itself to, as well as limiting the charging current.
With NiMH, the charger doesn't actually know the voltage, or at least I've not seen one that does. It just charges until it sees the battery resistance spike / charging current drop, which indicates that it's (probably) full. You generally want to charge batteries at a low current, as heat damages them, but that makes it harder for a charger to spot the current drop when a NiMH is full. They can do it, but it's a slight risk factor, and some "smart" chargers - I'm looking at you Nuprol - are fit only for throwing in the bin, before they burn your house down.
A 1600 mAh, i.e. 1.6 ampere-hour battery charged at 1 amp will take at most 1.6 hours to charge from completely empty to full, plus a bit more for heat losses. At 1.6A it should take an hour, At 2A, it will take 0.8 hours or 48 minutes, and so on. But batteries rarely get that empty, so those are upper limits. Keep an eye, or rather a hand, on the battery while it's charging, and if it gets uncomfortably warm, stop charging rather than pushing it too hard.
Or skip all that and get yourself some lithium-polymer or lithium-ion batteries.