Our Wash is safe. We do not use the traditional brushes that others use. We use a closed cell foam pad with polish infused, state of the art chemicals that actually polish the car as it safely cleans. We have never had any problem with scratches.
I put my SSR thru. No scratches or swirls. I think you'll be fine.
Hard to say. I think any carwash with brushes could have some fine particles in them from other cars. You could ask them how often they change their brushes. I guess the safest bet would be a handwash.
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