Dr G. Please feel free to chime in. I recently moved from a complex to a private home. I have a black Silverado with Gloss Coat. Being in a complex without access to a hose I always washed my truck with ONR. Being excited about having a driveway with a hose I did my first wash at my new house. I did a traditional wash and water spots everywhere. I purchased a bottle of MDR and it worked ok. Maybe 70% removal. I remember somebody posting about using Paint Prep before MDR with fantastic results after MDR not fully removing water spots by itself on a Gloss Coated Vechicle. Thoughts?