ChefsChoice AngleSelect Diamond Hone Knife Sharpener #1520:
Finally, a Chef's Choice sharpener that does BOTH Asian (15-degree) and European (20-degree) edges!! This is essentially two sharpeners in one: the first stage is a diamond sharpening stage (regular, not coarse) at 15 degrees for Asian knives (or any knife you want to put a fine edge on, like a thin fillet knife for example), and the second stage is the same, but at 20 degrees for standard strong and durable all-purpose European style knives (great for a chef's knife for example). The third stage is then a final stropping/finishing stage (it doesn't really affect angle, so you'd use it with any kind of knife). So the idea is that you'd use stage 1 and 3 for an Asian-style edge, or stage 2 and 3 for a European style edge. I think a secondary benefit of this approach is that you're likley to get even more years from this unit before the wheels wear out (eventually the diamond wheels wear out... customers have been reporting about 6-10 years with average home use with the older models) because you've essentially got 2 first stage wheels to work with.
If I were to compare it with the other models, it's like the second and third stages of the model 120 (but with a choice of TWO second stages really), or a model 320 with a choice of two 2nd stages. So yes, you're missing out on the coarse first stage of the 120 and the ability to make a 3-stage (EdgeCraft calls it a TriZor edge) edge or to grind out a VERY dull or damaged blade. Is it something the average person is likely to miss? In my opinion, not really, but if you have a standard German style knife collection (Wusthof, Henckels, etc.) the model 120 will probably be a better choice as it offers the choice of using that first stage, and it's a bit cheaper.
Here's the manufacturer's description:
The Model 1520 is the world’s most versatile sharpener. Designed to sharpen Asian, European and American style knives, you can restore and recreate both a 15 degree angle on your Asian style knives and a 20 degree angle on your European and American style cutlery. Engineered to provide astonishingly sharp edges using highly precise knife guides that automatically position the knife, it is an easy to use, must have sharpening system. The multi-stage Model 1520 features 100% diamond abrasives and patented flexible stropping/polishing discs that create a "gothic arch" edge structure recognized for incredible sharpness and durability. It will quickly and easily sharpen virtually all quality cutlery including American, European or Asian style household knives; fine edge or serrated blades; Santuko and traditional Japanese style single bevel edges including the thicker Deba style blades; as well as sports knives, pocket knives. Three-year warranty. Assembled in the U.S.A.
NOTE: be sure to read the directions for your sharpener BEFORE trying it out! It contains absolutely essential information to make sure you get a good edge and do not damage your knives.