I used mine for the first time yesterday. It got a 12" Made-In chef's knife (MoV HRC 59) ridiculously sharp. I could easily get a burr on the opposite side after the first 120 grit shaping pass. Followed the instructions to flip knife and do the same number of strokes, then flip and move to the 600 grit, repeating the process for the hone.
Another cheap chef's knife I tried (Golden Eagle - Japan) took forever to shape the first burr, but eventually it got pretty sharp as well. Harder steel I'm guessing.
As for the sharpener... Overall, it's great.
Criticisms:
The clamp could be better - I found the blade moving around a bit, despite having tightened the knurled nut down pretty hard. Not bad, but enough that I had to pay attention. Maybe I was putting too much pressure on the stone holder. I had to keep some pressure on it to keep it flat against the blade. I'd like to see the stones be twice as wide.
My biggest gripe was with the reversible knife holder itself: The magnets that hold it into the angle setting riser aren't really strong enough. I found myself keeping a thumb on the knurled nut to hold it in place. That put my off hand too close to the blade for comfort. I'd like to see a redesign to get rid of the magnets and put some sort of locking collar on that part, keeping the push-button rotation in place. Or they could put an extension that lets you press the holder against the angle setting riser.
Other good points:
The base is plenty sturdy, and on the right surface the grips keep it quite stable. I found myself holding it down anyway, but I don't think it's necessary if using the right amount of pressure on the stones.
The rubber O-rings on the rod that holds the stones work great. They let you adjust the back-and-forth travel of the stones to increase/decrease the radius of the stroke depending on blade length. Another benefit is that you can use the entire surface of the stone, keeping spot wear to a minimum.
The rod has a magnetized pin that sticks into a hole in the riser. Great idea. Pull the rod out, rotate the holder, put the rod back in. Easy peasy.
The overall design holds the angle between the stones and the blade quite well.
Overall, for just a bit over $50, it gets the job done quite well.
I'm going to sharpen my Wusthof steak knives today.