I had my top of the line escourt passport installed in my 2008 M3 convertible by a escourt authorized shop. It is in the front ashtray so I can shut the lid in Conn, Va, etc.
Must have amplifier and extra speaker. With the top down, radio on at 125 plus have to hear and light does not grap you right away. Was doing 125 plus in Va and did not hear it immediately. Paddle shifted down but he still clocked me at 95 in 60 on the interstate down the Shanadoah valley of a sunny, dry day. 90 or above is manditory reckless driving. Got lawyer local on internet who bargained it down to speeding, $1035 including costs, plus his $1500 cost. On the plus side, no reckless driving on record, no jump in insurance and he handled it all while I was in Europe. I just phoned in my credit card.
Nw I have to be good and save my cash for the Ericsson M480 Titanium Exhaust.