See, the trick is to never let enough brake dust and road grime accumulate on your wheels :xyxthumbs , so you will just have to wash your wheels every night.
Ha, just kidding. I have used AIOx2 and SGx2 on my wheels in the past. When they got really dirty (with brake dust), I would use McGuires Gold class, with a touch of Dawn. The combo works pretty well, and removed all of the brake dust.
The hard part was getting my fingers into the small holes on the BMW wheels (man, that was the hardest part of cleaning). It used to take me almost an hour to clean my wheels. Now, I have big 17" wheels, which are a breeze to clean. I am about to order a set of 19" wheels for the car so that should make my wheel cleaning even easier.
Oh, I almost forgot. I have used Eagle One's Mag and Wheel polish. It is specially formulated for wheels. It looks great as well, if you are looking for an alternative to Klasse sealants.
Best regards.