It depends on how much you want to spend. I'd recommend a Baratza burr grinder. The entry level Encore is excellent. I've been using the Preciso (which is essentially the same as the Virtuoso) The big difference between the Encore and the Virtuoso is power and as a result, the Encore takes roughly twice as long to grind the same amount of beans when compared to the Virtuoso.
If you want to go crazy, you could go for the Mahlkonig EK 43.