I use QEW almost exactly as you described but have added a couple of things to the process. If the car is not very dirty I usually add a capful of QuikShine to the wash and don't even do a QD when I finish...now we are really saving some time. I also take a sprayer bottle and fill it from my wash bucket before I start and use it to spray the rocker panels and other particulary dirty areas to make sure they are wet and have a chance to soak for half a minute or so.
There is definitely a confidence curve involved with using this stuff but I keep using it on dirtier and dirtier cars and it keeps performing without marring the paint. It is really nice to drive a detailed car when it has not been above 20 degrees. People definitely notice and scratch their heads.
Of course I should have known that any product that Scottwax has used for years must be worth trying.