Paul A posted this in the General Lexus forum too.
Its important to note, that over time a carwash with anything that touches your car WILL scratch the paint. They're too harsh and they don't get cleaned. I agree that they are better than not washing a car at all, but they are no substitute for learning how to do it yourself and purchasing the right tools. I can wash my car in 30 minutes, about the time it takes to drive to the carwash...wait in line, let them towel it off, and come home. The end result is much better, safer, & cheaper.
Touchless washes won't scratch, but they use harsh soaps that strip wax, and they don't provide you a clean paint surface.
One thing people don't think about is hiring a detailer to wash the car for them. They can do it at your home or office, and sometimes only cost a little more than a tunnel wash...or even the same amount...