I've run Pole Positions on 3 - BMW's and 2 Minis and have tried other tires as well. Highly recommend the Pole Positions!
If you're running them on a Cooper S be aware that the fronts will get eaten 3x faster than the rears but this will happen regardless of what tire you use.
This tire is perfect for BMW's as it performs well, lasts well, is quiet and looks great. It's an overall '10' for value.
We're putting the RE970 Pole Positions on my wife's Audi S4 because we can no longer get the RE050A... will leave a review after we put a few miles on them.
Beware too that there is a RE050A that is NOT a Pole Position... these are simply not near the tire the Pole Position is... make sure the sidewall states Pole Position.