i had a radar detector in my beamer up until the other week before i sold the car,it was the best thing ive ever had,it saved me on so many occasions its not funny,i bought it with the car,the guy who sold me the car was an auto elec and he sells and fits them,they are not cheap,they cost $1800 fitted and they sit in behind the dash and you cant see it,to dc it you just pull a small jack plug from under the dash very easy to do.
the unit let off a few beeps if it was within 800m rangebut within 600m it was beeping constantly,within 400m it was going off its head,this unit is also connected to your radio so when your within 400m range it turns off your radio till the radar has past that metre mark,the only problem is now i have to be very carefull cause im used to driving a bit faster than normal,i highly recommend the unit and if anyone is interested in this unit they can send me a pm and ill foward you the guys business name and you can buzz him,like i said its not cheap but for the last 3 years im yet to lose a point.