I used turtle wax f21 tire foam and it brightened my faded mats to near new without being slippery. I was gonna replace them anyway so I said why not give it a try. It looks really good. Here's a pic of my donor cart that received some over spray of f21 when hitting the rear fender covers and bag well. I had them sitting on there while I sprayed them down.
This last pic is of my cart that I sprayed about two weeks ago. Before I sprayed it it was severely faded like the donor cart mat.