Thanks for all your answers.
Yeah insurance companies will kill you if you're under 30 and you drive an 80k sports car. Ahhh the cost of being young and well off :-)
I'm getting my M next summer and I'm trying to find the best deal. I'm currently 35 with a good record. I'll call my insurance today to see what they tell me. I believe I'm paying around 1.2k on my X3 so if it could be under 3k for both that would be awesome.