I think a pen won't do the job well and you never know which pen is genuine. There are lot of scratch remover pens in market mostly fake. I think a good scratch remover kit from Turtle/Meguiars will help you only for minor scratches. Just do wax after you use scratch remover. Once, I tried Waxpol Cleaner and Polish. It was not too good but average to remove minor scratches as I bought it in few bucks. Used it only over scratchy area and then waxed my car. The result was good and shiney !