I think this stuff (vinyl coated particle board is "melamine") is great to paint. I have actually used it in several pieces of furniture that I have built because I had about 10 sheets of 3/4" left over from building some store fixtures. Paint that I have found works fine on it is both spray paint and epoxy automotive paint (two part). I just scuffed up the surface with 100 grit, dusted and painted. I didn't use primer and it has lasted years and looks great.
The trick to using this stuff is in using good t-moulding edging and actually knowing where to use it and not use it. I have used it in a piece that I sold for over $5,000 but never for anything structural that could sag or fail.