I don't have any experience, and after a few grooming horrors with my babies at the Rainbow Bridge, I have done all of my own grooming for many years. There was a thread on here a few years ago that I learned about these dryers. I shared the story with every dog owner I knew personally. It completely horrified me. The photo in this thread is difficult to bear, so I'd advise not to open it. This story really awakened me to this. I don't think I'd trust your groomer after this. Perhaps they monitor the dogs when using them, but they really scare me now.
http://www.yorkietalk.com/forums/sic...n-graphic.html