I rode a 2009 P4 with the upgrade brake and it still doesn’t stop well. I had to squeeze REALLY hard too and I was still sweating bullets coming down a hill with a stop sign. Also, it looks like one side pushes against the wheel instead of both sides equally applying pressure to the brake surface. There is also a washer or something metal that is REALLY close to the brake pad and therefore real close to the brake surface. Kind of scary.
I equate it to the difference in braking with a Honda Civic versus a Chevy Suburban. Kind of mushy and definitely a delayed response. You have to plan ahead for your braking.