Saw some Facebook posts from pro installers who've used Carpet & Fabric on leather and vinyl with great success, so I decided to test it myself. Last weekend I was prepping my pontoon for winter storage and cleaning the vinyl seats. Even though is spends the summer in a covered dock, it gets all manner of spider spots, bird crap, etc and if not cleaned weekly, the spots can bake in. I've used Power Clean, ONR, and Marine 31, but they all require multiple applications and scrubbing. Carpet & Fabric worked the best, spray let dwell, rinse off - spots dissolve easily. Even though it contains protection, we then coated with Protectant Plus for the winter, our SOP. One caveat - don't spray on metal, it leaves streaks that don't come off easily. An earlier poster had the same issue with Power Clean, though I've never had that happen. I haven't tried C&F on leather, but will test that next.