Mezzaluna, I don't like electric knife sharpeners but occasionally see them being used and can appreciate the fact that there are lot of people who don't have the skill or desire to spend the time it takes to hand sharpen their knives, including some who use them professionally for 8 hours a day. Electric sharpeners are easy to use, fast and produce a very usable result which is all some folks want, but they do have their limitations and problems.
I am a collector and don't like anything that hurts them and electric sharpeners distort the blade shape in ways that upset me. For starters unless you are a robot, the very even curve on your knife's blade will gradually become a wavy line and their is nothing you can do about it with electric sharpeners like those made by Chef's Choice. In fact they can't even reach the first 1/2 inch of the blade closest to the handle, so all the metal they remove starts 1/2 inch from the handle. Use it a lot and you will get a dip in the blade starting at that point, and there is nothing you can do about it. If it's a knife you use for chopping, now part of the blade won't touch the chopping block.
I admit many people who use stones, and steels similarly distort their blades shape, so it's not like you can't go wrong doing it the old way, but it's impossible to do a real good job sharpening a fine knife the "right way", and maintain the designed blade shape, with the electric versions.
However if you're a butcher slicing meat for 8 hours a day, and want an easy way to make your knives quite serviceable without having to hone or steel them yourself, that Chef's Choice sharpener might be just what the doctor ordered. In that case you're not using expensive chef's knives, and you probably don't care if your inexpensive commercial quality butcher knives look like heck, and need to be replaced every few months.