I'm with you on this one, always wonder how they have managed to get such a clean car yet their plate is manky.
My Mrs is looking at getting the 4d plates, I'm not 100% sure of them but her car so up to her.
I got 4D plates but just didn't like them on the car and went for 3d Gel ones instead. The rear looks especially daft when the digits cast a shadow at night from the number plate light above. Just felt they looked a bit chavvy and feel the 3D gel ones are much, much better. Each to their own though.