I've always used whetstones for sharpening my single and double-bevel Japanese knives, but I must admit I lack the skill to get them completely back to new condition uniformly along the entire blade. I've also never been particularly fond of electric sharpeners. But at the recommendation of a friend I recently acquired a
Chef'sChoice Asian Sharpener from Williams-Sonoma.
The directions for restoring to factory edges are a little obtuse, but once followed result in wickedly sharp blades all along the blade. If anything, the blades may be sharper than when they were purchased. I just use a ceramic steel or metal steel depending on the knife before each use and it is like slicing through butter!
I am extremely pleased with this purchase, especially since it is from Williams-Sonoma with their unconditional lifetime warranty. If you don't agree with my recommendation, just return it - no questions asked. But you really need to follow the instructions precisely. They're not intuitively obvious.
Bill/SFNM