Well, a-hem, OK you all know Im a newbie and have never owned a BMW or convertable for that matter. When I first applied blue magic cleaner, I followed the directions but was disgusted at the results. Applying it with a towel resulted in thick VS thin areas which ultimaetly resulted in spots. I figured Id get a spray bottle and mix it 2 parts cleaner to one part water. It sprays on evenly and I seem to wipe it easier with the towel. It covered great (evenly) and cleaned the top nicely.
Just wanted to pass on something to you all to help you maximize your "detailing time".