I know I am a few years out of date to revive this thread but I use Williams waterless wash and wax and I must say I am more than happy with it. As long as you do it properly it will be fine. I have yet to have swirls or paint scratches on mine and the added bonus is it cleans the windows including windscreen without any after affects and it also brings the chrome up as well. I also give my leather seats a quick rub with the buffing cloth after doing the car and this brings up a nice shine on them as well. I works well on alloys as well, although I do use different cloths on them from the rest o the car. I had heard all the good and bad points of using waterless wash and wax but living in a flat and not having use of a hosepipe I used to use the two bucket method, and because I am quite obsessive about keeping my car clean found I just didn't have the time to do it this way as it was taking me bout 2 hours to get the finish I wanted, so I thought I would try this, so bought an average make and was immediately impressed, so much so that I invested in a good product and never looked back. I can do the entire car in around 45 min to an hour. However having said all that, each to their own. All I would say to anyone is try it. If you don't like it or its not for you, just go back to your usual method. It will not harm your paintwork and you might be pleasantly surprised.