Around here (Buxton, Derbyshire) you'd get pulled within a mile with them plates, and a £30 fine.
Bloody Omega traffic police are so strict, and they got number plate recognition in the car scanning EVERY nearby vehicle (front & back cameras!) which wouldn't read the plates so they'd be straight after you.
Depends on what area you live in, but I wouldn't risk the plates on the back (as that's where the copper is more likely to be following you from) but just the front where they got less chance of pulling you over.