The power sharpeners are fine for the guy cutting firewood next to his house, or the cutter who uses his saw less than 4 hours a year. The downside is once you use them on your chain you have to keep using them. A file will give you way more life in your chain and easier to touch up every time you fill up.
Interesting point as to the original post. I'll stick with the little plate to slap on and file them down but good to know!
