Was a Spanner Jockey then joined the old bill.  the 3.2,s were very good, plenty fast enough and more than enough power.  When i first came across them we still had an old 3.0 senator straight six, avery nice engine indeed.  The autos were/are good cars, but failed to take the abuse that the manuals could.  I think all the Omegas are out of Police circulation when they decided that BMW offered a better package in the car and servicing etc.  They put a high price on their cars being seen and used by Police.  Vauxhall have nearly lost all the police contracts, with all but a few old shape astras still waiting to be replaced.  Seems Ford and BMW are the way to go.  
I have driven both the marked estates and the unmarked saloon versions of these cars.  The saloon MV6 plain cars were the best by far, although i would never want to by ex-police cars, servicing is kept religiously but they get used hard.  None of the cars we had were 'chipped' as some think happens, neither do we have a button which changes the lights to green.  the most modification i ever knew of was rear suspension of the traffic cars, and sometimes better brakes.  They come from the manufacturer as a standard, or sometimes a Police Spec car, and are converted to take the radios and lights hence the missing radios and holes all over the place.  
Got me a dirty diesel now.  I still drive the high power cars at work, so no need at home really.