Best money we have ever spent. Yes, you cannot use them on the grid but you can use them in the paddock. If your paddock spot is close to the grid ( clever you! ) then they are worth ever penny of what they cost. Going out on HOT tires is unbelievable! Look at it this way. Even if you have a pace lap and your tires are at 180 degrees when you go out and you lose 50 degrees on the slow pace lap the tires are still at 130 degrees. Works for me!