Well, you can get to a gloss finish by squeegeeing out resin under Mylar and then peeling it but that still doesn't get passed the fumes. I think they're toxic, based on the life of an artist that passed at 50.
https://duckduckgo.com/?q=epoxy+polyester+resin+toxic+fumes
It's just what I said, not a fan. No big deal.