I use a Lansky kit on all of mine. Works great and doesn't take long.
That's two votes for a Lansky. Pretty hard to beat.
http://www.amazon.com/Lansky-Diamond-Deluxe-Sharpening-System/dp/B000B8L6LS/ref=sr_1_1?s=hi&ie=UTF8&qid=1343756848&sr=1-1&keywords=lansky