When I did collision work I had a few airfiles (Viking and CP) and also an orbital airboard and sold them after buying an 8" mudhog, I never could get anything shaped reasonably well with an airfile.
I used a mudhog at a shop I used to work for. I forgot about them. I usually get off the airfile when it gets close and switch to long board by hand. Could be why my shoulders always hurt! Thanks for the info.