Our X3 w/Sport came with Michelins
They have 22k miles on them and show no signs of unusual wear or make any noise. From the looks of them, they have at least another 15k of life left. When we bought our 00 328 new, it had Bridgestone tires on it. We got about 15k miles of use out of them and at the time we replaced them they rode hard and were noisey. I've learned to stay with Michelin over the years. They might cost a few bucks more but if you can afford the car you should be able to afford the tires to with it.
06 X3 Silver Gray/Black / Sport / Prem / Step
05 Dolphin 5376, (that's 37' of fun)