We just sold out boat and had some leftover Interlux Brightside Polyurethane paint (Hatteras White... which is an off-white and not the mega-white it was prior) that we used to paint our faded coping just this past weekend. It covered easily. It's a paint designed for the marine environment and should hold up very well. Only did a light sanding (to prevent too much dust from going in the water) and wiped with acetone. Used a nice brush. The results are fantastic. We may do another light sanding and second coat, but the jury ius still out on that.

Hope this helps.