Did this on my Vibrant cover.
1st try, sanded down the gloss but none of the paint, plasti Dipped just the outside, edges came up pretty much immediately.
2nd try, sanded the crap out of the edges and lightly on the inside, 2 coats inside focusing mainly on the edges, 3-4 coats outside focusing mainly on the edges. So far its held up pretty well over the last 2 days including one trip tumbling in a backpack.
I don't think it matters how many coats you put on as long as you prep and sand.