Mr. Incredible....my 2 cents worth.....I think you need an alignment, preferably 4-wheel.

I'm a hard/spirited driver in my '05 4.4i. Got 40K on first set of Diamaris and Goodyear replaced with same. Cupping got bad (with associated noise) at 15-20K and I went back to them blaming their alignment. My understanding is that cupping is an alignment problem and it won't get better. Because I got half the life of the original set, they replaced at half price and credited their alignment charge to the BMW dealer's charge for a 4 wheel alignment. I was fortunate there. That set was installed and alignment done at 60K with perfect performance and even wear for 40K and now ready for next set.