There was mention further up this thread that KZ would eventually hold the records at most tracks. In response to that, and I’m not sure how relevant it is to the US but we have an “Open Performance” class here in AUS where basically anything goes, but there are weight differences to keep it fair.
At an event recently here we had KZ, twins, and a couple of others, racing on the same track together and a twin won.
it was amazing to watch, The sound! It was like the world was ending.
So if you guys have a class like that over there I think it would be a tough call either way, which is half the fun!