I've used Lasky diamond sharpner for years with good success. Got my first one when I realized I couldn't sharpen an old Gerber knife enough by hand to cut butter.
On longer knives I put little marks where I mount the clamp so I can get it back in the same places every time. That greatly reduces resharpening time. Getting that proper consistent angle keeps the knives sharper a lot longer too. Something I just can't seem to do free hand.
