Nottingham police use a dark blue BMW M5 on their strech of the M1.. i had a friend done by them doing 99.5mph over a period of 1.5miles... Lucky he still has his licence! Also in Leeds I have seen unmarked white bmw 5 series with blue lights flashing in the grill and rear screen patrolling the M1.. Not to mention Ford Galaxy undercovers although not sure if they are used as a persuit car... U have been warned!!