Review (5/5): Works as well as pricier models!
I have to admit that I was a little leery of this tool, but I took a chance and was glad that I did. It works great at removing calluses and dry skin on the sides of your feet. It runs on batteries, and the ones that came with it ran out of juice rather quickly. Once I put a fresh set of batteries in, I've used it 4 times with no noticeable decrease in the power.
After the initial use to get rid of those pesky calluses, I've been able to use it for short periods of time once or twice a week as maintenance.
My only advice is to follow the instructions - this has to be used on dry, clean feet for the best results.