I went to the AQS show in Des Moines and bought a $29.95 blade sharpener in October (Martinelli). If the blade is dull, it works great BUT I always seem to nick the blades, then the sharpener is worthless!!! The salesman told me that ordinary blades become flat just because the steel or whatever the metal is, bends slightly and becomes flat on one side and thus forms a nick. Of course, what a coincidence, he had blades that wouldn't do that! HA! (They do last a little longer.) Anyway, when I first got home the main rod in the sharpener was bent so e-mailed the shop I purchased it at and they sent me a whole new unit so have 2 extra sharpening "stones". Honestly I wish I had the $29.95. I too wait and get a 5 pack at JoAnn's with a 50% off coupon. :( SewinSue)