I have had one tore apart and have been messing with it for a while now. Only problem is light leakage and resolution of the overlay. You'd have to make sure that if you did print it, that you would have some way of making sure that the parts you want dark are blacked out and printing black on white substrate will not yield this effect. I've done one but unfortunately it never made it into the car because it needed some work and pulling everything out to do it right afterwards wasn't appealing to me.