Do show plates have the reflective backing?
I had an Arnold Clarke one on mine but as they are so c*** I removed it straight away and the buggers had the cheek to mention why I didn't have it on there when I took it back in for a service 3 months later!!!
they are not illegal simply because they are show plates, they are only illegal if they break the rules. plenty of show plates can be perfectly legal for road use, mine always are, i simply get normal legal plates made but without the maker's details on them. it is only illegal to make them like that for road use, but using them on the road is perfectly legal. if it wasnt then many people who had a plate made before the law came into effect would have been using illegal plates, even the original plates were often blank before the law and they arent suddenly illegal to use on the road.
only for road plates, that is why plates without the postcode are sold as show plates, and are perfectly legal. the law only applies to making plates for road use, not using them on the road. its a well known and well abused loophole.
FJ Chalke in Somerset do a similar thing except they stick a little chrome plated dog on the back of all their cars.
If I went to pick up my brand new car and the idiots had vandalised it like that I would demand a completely new car, just to make a point.