I've used "scratch remover" (fine cut compound) frequently for years and have never had a problem. You need to make sure the surface is clean, and then apply it with a microfiber applicator or rag. Buff with another clean rag and then apply wax.
These so called miracle scratch removers are a joke. The only thing that removes scratches is a product with an abrasive, or you can fill them in by repainting or re-clear coating. McGuiar's Scratch-X works well on the small stuff, and their Ultimate Compound works well for the bigger stuff. The only way to fix scratches that are down to the primer or the metal is to replace the paint. These miracle products won't work.
I've had good results with the turtle wax premium grade polishing compound (in the upside down bottle) so I imagine that the PG rubbing compound would be even better for removing scratches.
The old white compound in the green tubs is ment for really old thick single stage finishes. It would leave some hazing on on a clear coat finish.