Not bad, worth it.
My white cars look and feel better.  I don’t mind it doesn’t turn the rail dust purple, I can see it. I sprayed it on, waited 4-5 minutes and rubbed with a cloth before rinsing.  Came out.  What it does on the wheels is amazing. The con, like others have said, the spray bottle sucks. Bad right out of the wrapper. You squeeze the trigger and you have to pull it back out for the next squeeze. The company must know that spray trigger doesn’t work. Maybe because of the chemical. It’s a shame a decent product is compromised by poor packaging.  Still, it’s worth it.  Smell is not bad. You don’t buy it as an air freshener. Smells kind of like coconut with a little aftertaste.
Rating: 4 stars