For hotcoats we recommend using Resin Research ULTRA Quick Kick Epoxy. The QUICK KICK version is a bit thicker and cures faster therefore provides a thicker hotcoat that stays on the rails better and doesn't drain off due to gravity. A thicker hotcoat will help prevent sanding burnthroughs.
We feel that Resin Research Epoxy is the best on the market. This is why we only sell Resin Research, it is a superior product in our opinion.