I also start with the barrels then work my way to the face of the wheel. I usually do 1 wheel at a time but different cleaners allow for more or less dwell time before drying on the wheel. I've just accepted that these wheels suck to clean and take longer than the rest of the car.
They are one of the best looking wheels for the E92 so I take the good with the bad.
One more thing, I've tried a bunch of wheel cleaners. I find that Meguiars is very good for the $. Since I wash my car weekly, I don't need expensive heavy duty cleaners.