Just brought my copen and she looked really nice on the outside apart from the know rust patches on the back arches which looked like 2 little dots. I thought before she gets any worse I will sand them down and tackle them. To my surprise the 2 little dots had spread a lot further and I was very surprise from a 56 plate that's done only 36 thousand miles. So have now sanded the back end down and treated the metal before it goes through. The rust did spread but didn't eat through the metal. Each weekend will be going through the car and rust proofing her.