I just purchased a 2008 Mercedes C350 and I really want to be careful with cleaning the wheels. It looks like P21S wheel cleaner is the safest choice. My question is how the regular formula compares to the gel. Do most of you stick with the gel or should I start with the regular formula? Also, I am ordering from Wisconsin where it is still quite cold. Do I need to worry about this stuff freezing? I plan on capitalizing on the frozen Fuzion special. Apparently it is okay for wax to freeze, But what about the wheel cleaner. Thanks!