We sold our first Xray car this week. XB4s took 1st and 2nd in 4 wheel buggy today and Friday! I got beat by the new one. They have been doing great on low/med traction blue groove right out of the box. They are holding up well too. I haven't broken anything in 2 months. At the rate I'm going I'll be getting a new car before I break or wear anything out!