The Wheels
If the product does have one downside it is BMW wheels with their brake dust. This was one thing I really wanted to see how it worked on.
The Test Subject - Front Passenger Wheel

Half/Half

Done, notice it has problems cutting through baked on dust

However nothing alittle APC and MF towel can't fix
Final Thoughts
A must in everybody's arsenal. Work great and leaves a nice shine. I love being able to sit inside the garage in the middle of the day and clean the car and not have to worry about the sun drying the water and leaving water spot. Also I stay cool and dont have to wash the car at 7 in the morning before the sun starts bearing down. Very easy to use and takes about the same time as with a hose. Probally will be faster as I get more used to it. The only two downsides I really notice is its inability to cut through some break dust and grease and its terrible smell. However keep some APC and MF towel handy and you are set.
I give it 5 stars.