My nails have never looked great, but my mom has beautiful nails. She likes the Revlon emery boards, and prefers the longer ones if we can find them. I keep probably two emery boards at any one time. My nails are generally too short for them to be of any use.
My mom uses her emery boards at least three times a week. Her nails are strong and grow in a nearly perfect shape, too. It's kind of irritating to see how easily she keeps those beautiful nails, but I guess mine are doomed since I work on a keyboard all day. That's murder on your nails.