I have the proper "stamped" black n silver plates on my purple mk2 escort, its a 76 reg and has passed its MOT with them on, been too a dozen shows and the plates haven't been mentioned by anyone, i even train with half a dozen coppers and they've never mentioned them, but then again, cause its an old car they don't look out of place, more modern stuff??? I think it depends on the colour, the white one above doesn't suit black plates imo, but each to their own.