The question of whether ONR leaves anything behind comes up every so often. This is directly from Dr G:
"Onr leaves polymers that are cumulative over time. Car wash does not leave anything behind."
ONR is paint safe and body shop safe as well.
I personally don't like the "blow dry" method - Understand the benefits of no touch, but my OCD finds it takes too long to get every drop off. I take care with quality drying towels and have no marring...
Guz is correct in no need to mask, but one suggestion - don't spray directly onto glass. We've found that Opti-Glass begins curing immediately and should be sprayed directly onto the pad and applied at once. Delay can cause less than satisfactory bonding.
There is a cumulative affect of using ONR, with residual polymers remaining on the paint. I can't speak to Car Wash (admit to never using because I was seduced to the dark side by ONR). I don't think there's any negative to washing with ONR, rinsing, then blow drying. But I also see no advantages, certainly not in time or resources saved.
A little understood/appreciated piece of car care is the different bottles and sprayers necessary. Optimum found this out the hard way when Carpet & Fabric Cleaner & Protectant started eating the bottoms of bottles (as I discovered on my cabinet floor) - had to buy a new formula plastic bottle. Optimum sprayers are not universal - we use a heavy duty model for Hyper products and even then, Hyper Compound requires a different sprayer than Hyper Compound...is hell on efficient flow in a distribution center. Dr G has that responsibility, on top of a few others.
OPP works great on plastic, vinyl, and leather - it's a cleaner AND protectant and should have no issue with Eyesight (it's not glossy). Opti-Clean is the stronger cleaner but does not replenish natural oils in leather. If necessary, I would clean the interior with Opti-Clean, then treat it with OPP.