Bm Command would work well for that.I have a customer with a large window sill, about 12 inches wide. It was painted about 10 years ago, so it is well cured. It doesn't feel sticky to touch, but when they set something on it, say a piece of paper, the paper will stick to it and leave part of the paper on the paint. I plan to prime it first with Stix, but not sure what paint to use on it. Does anyone have any suggestions?