That's because in the US all they are interested in is drag racing how often do you use brakes I went out in JP's black beast you seriously would not want to be running stock UK's on a big HP car and drive like he does. All I know is what I gained from personal experience with UK's as I said before even if stopping distance does not improve the point in which they fade would be different ,if stock brakes are so good surely company's like brembo ,ap,ksport,kad,stoptech, would be out of business by now.
Why would the bias be any different to the brembo 14" kit that mvp sell for 4k which look like the same calipers? I am pretty sure brembo did not make a one off caliper for a supra its the same one that's fitted to the AMG's as well, mvp do not sell it with a bias controller so who is to say that is the same as the stock bias?