We had the brushless come to our club late last year, when people visited from another club, and we still have people running the sport tuned.
I had one of the quicker sport tuned, a change to the hobby wing and with a car thats still not as quick as it should be and I can lap around 2 seconds quicker. There is still another second to make up to get to the front of the pack.
But the change has made the racing much closer at the same time.