I don't do any waterless or rinse-less washes unless the car is foamed and pressure washed first. Also, I clean the wheels and tires first conventionally. I'm not trying to save water, but it does save some time. If you do this & lube the panel with waterless wash before touching it, it's not much different than a regular wash. You wont get scratches, but you wont save as much time. As, then panel and towel will both be wet and soaked with lubricated solution before touching the panel. Any detailing task takes me A LOT of time because I'm working on my own car and take every precaution. But, I have found some advantages of rinse-less or waterless wash.
1. No water spots. You can pressure wash the car outside, and do the rinse-less or waterless inside away from the sun.
2. Car dries faster and more completely. Even though I pressure wash first, most of the "drips" come out while you are doing the wash process. Also, I do the wheels conventionally first, so they dry completely while doing the rest of the car. Tires are also dry by the time you finish. This is where a lot of time is saved for me.
3. It is faster (not too much) because you spend no time rinsing, getting the hose, and laying it down. Also, its faster because I don't have to hook up DI water filter for final rinse.
4. You are able to work in very cold temperatures easier without getting (as) wet. As you can work anywhere you can park in shelter. You can do your pre-rinsing outside and pull car inside to wash. Also, you are able to pressure wash at one local (coin op) and rinse-less wash at another (inside away from cold)
5. Since I pressure wash first, lube the panels with waterless wash, and clean wheels and tires conventionally first, the results are the same if not better than a 2BM wash. "Better" because you are left with no water spots. Also, because your not rushing to get done before the water dries.
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