I got a flier today from Harbor Freight, which includes a Chicago Electric chain saw sharpener, for $38. Except for the color, this looks the same as the Nick-the-Grinder I bought a few years back, also from Harbor Freight, for about $50 (as I recall.) Since that time, two friends have borrowed my grinder, and both ended up buying their own for about $60. Both have more than recouped their cost in sharpening fee savings.
I can't say for sure that the orange colored Chicago Electric unit is as good as the dark colored Nick the Grinder, but they sure look the same, For the price, it sure looks a good risk.
I'm not a shill--just a helpful bystander.