I won the green trail ridersrasp. Love it, for our big horses it smoothes any chips off and I use it on the minis too. The green one I have has interchangeable blades so I can get the courser blades which seems to work better for most people.
I have tried one that a friend has, I think if you just had a small chip or something it would be fine, or just wanted to maintain between trims it would be fine. I don't think it would replace a true rasp for the heavier work.