Sorry to say, I have--once, largely due to weather, availability, etc. And even with just the one pass through, I can make out some very fine scratches from the whirly-gig fabric flappers they use--and this was at a "high-end" car wash. Never again. Never again. There was a post somewhere on here about how to wash a car--had some very fine description of how to do it right: two bucket technique, etc. That's the route I'm heading from now on. Might use the high-pressure-spray-only places in winter if I have to.