I was looking through PaperMart and they have poly ribbon and satin ribbon and very good prices,, has anyone used either of these on their cakes? the poly is waterproof so im thinking it may not soak up the grease like some ribbon does.

I'm not sure what poly ribbon is but I used satin ribbon on a cake recently and had no trouble with it soaking up the grease. Maybe it depends on what type of buttercream you use or the color of the ribbon (mine was black) but I didn't have any problems with it.