This is a great forum and I've learned a lot since joining recently. Haven't had much I could contribute but re personalised / illegal number plates I do have some 'insider' info!
When she's not being a 'plod', 'jobsworth', harassing law abiding motorists or having fun racing on blue lights to get back for a tea break (+ all the other stereotypes) my wife is a traffic police officer (proud owner of new Starlight Blue T6 conversion and a personal plate). On most shifts she and her colleagues will have been picking up body parts from another fatal RTC, informing a family that their loved one isn't coming home, risking their lives dealing with RTC's on motorways or been in a pursuit to arrest ATM ram raiders / car thieves etc. On those days you will probably sail by with an illegal number plate.
On other days an illegal number plate might make you stand out from the crowd as worthy of a stop check when combined with another minor traffic infringement or you might be involved in a no fault traffic incident.
If for any reason you do end up interacting with traffic police they won't ignore the illegal plate (they can't ignore it). As mentioned previously that can mean up to £1000 fine, you will be given a ticket to get a legal plate fitted plus the DVLA will be informed. It is a condition of buying a personal plate that it is displayed legally so the DVLA have the option to cancel it (and often do).
Being married to a 'cop' and being ex police myself, as you might expect, respecting the law is part of our personal values so we display our personal number legally. A practical reason for a legal plate is that,should your pride and joy be stolen, with an illegal number plate it is harder to track on the network of ANPR cameras and less likely to be recovered.
If you do get stopped and spoken to about an illegal number plate or any other minor offence, from personal experience of my policing days, saying things like "haven't you got any real criminals to catch" won't help your case!
