I have one, but it has never been taken out of the box. I got it when I bought my car, but never installed it after being advised that it may cause more damage than it would protect from (heat, moisture, etc.).
Most people say to clean with soap and warm water. However, you might consider whether or not you really want to use it. If you do, make sure you take it off in wet weather. Rain then heat = paint problems down the road.
Most people say to clean with soap and warm water. However, you might consider whether or not you really want to use it. If you do, make sure you take it off in wet weather. Rain then heat = paint problems down the road.