here in the US i have raced several classes of scale hardbody cars: true mid 1960's era cars (Cox, Monogram, K&B, etc), BRM, Scaleauto, and H&R Racing chassis with plastic model kit bodies. Overall, all of these classes were fairly similar in lap times, fastest being either rtr Scaleauto and the H&R Racing classes. I am surprised that hardbody real scale racing is not more popular with kids at raceways. Probably due to how building plastic models back in the 60's and 70's was more popular then, and kids today play with their cell phones. A Scaleauto car, out of the box, with their foam rubber rear tires are great to race- very evenly matched. However i have seen that there were two issues when raced: racers pushed the cars too hard: way too many deslots, too many track calls, too much body damage, and complaining of the high cost of a car, especially after damaging the bodies. Revert back to issue #1: slow down, don't deslot, and the car bodies last as long as you want them to. So if we raced them as the Germans race their beautiful CanAm cars, it would make for a great new series to race.
Unfortunately, all of that racing has come to an end for me. I just rent track time a few times a year, or adapt these cars to my home Carrera track with silicone rear tires. Not as much fun running them alone compared to a full 8 lanes of racing. Now that I am retiring maybe I will move to Germany and race Can Am