Paint will be the most durable, but vinyl will give the surface a more polished and even-looking finish. You can make it look pretty damned nice with just paint if you're willing to do the prep and post work though. Even if you go with vinyl, you still have to paint it before you install it. So I would give it the best paint job you can, then decide if it's good enough. If it is, polish it up with Turtle Wax Polishing Compound and you're done. If not, or if you wanna go the extra mile, install the vinyl.