The track I run on is hardpacked dirt with a healthy dust of topsoil that makes it pretty slippery. This past weekend, my Losi Step Pins had no grip. I tried someone else's AKA City Blocks and they were a tiny bit better, but still sliding around. I have a set of Silver Taper Pins already, but no wheels to mount them on. The silver taper pins come with standard soft foam instead of the medium molded foam of the other Losi tires. Maybe those would do ok from you description about the track surface since the surface is pretty hardpacked and abrasive. But I might need to pick up some firmer foams from your description. Even though it's a pretty hardpacked track and it's getting pretty warm, people still run soft and supersoft tires on it. I don't know how quickly they wear though. I tend to run harder compounds just because I can't afford tires as frequently as others.
Thanks guys.