I ran the USGT Spec motor today on a medium size asphalt track. My first impression was it's slow, but after gearing it taller, I think it's fantastic. Everyone was very equal down the back straight. I geared all the way to 3.13 but ran out of gears. I ordered some more gears when I got back from the track, I'm going to try below 3.0 to see if that works ever better. My motor never even got hot, I could put my thumb on it and feel a little warmth after a 5 minute race.