Actually, yes I was one of the first to have the FM10's. If you check on their site, they have my car with the FM5's (my brothers) and they also have me mistakely as a 930 also with the FM5's. You would think with this much press they would throw me a discount.
From constant use as track wheel and being driven in many times rainy conditions, the wheels build up an accululation of track dust, brack dust, and grease that collect in all the crevices. I can't usually get to them until the next weekend so this sticks pretty hardily to the bare aluminum lips. After about 7 years of this, it gets harder and harder. Still look reasonible clean. .