Do Drill Doctors Work?

They look kinda cheesy to me, but I've never tried one. Are they any good at all or should I save my money and get a really good one that can sharpen end mills and stuff too? My eyes aren't the best so its tough for me to sharpen anything on a bench grinder and I figure it would be cheaper than sending them out.

I like it... I use mine alot so it's time to change the stone.

Work great, resharpen very time I use a drill, so always good to go!!

I've had good success with them, you can use a bench grinder too.