I was so close to getting a different E85 M in the same colour, but the dealership that had the car for sale, promised to call back and we gave them the benefit of the doubt the first time round. We explained how we were in Oxford, so it would be a 150 mile round trip, so we were serious about wanting to purchase the car, yet they still didn't bother calling us back to talk about what sort of price the needed from the car and going over the details of the factory JCW Mini we wanted to trade in! So in the end there was one only 17 miles away, which is now my M.
I think the Carbon Black is an ok enough colour, but there is just something about a Z4 in Montego Blue that just speaks to me. There was another 3.0 E86 in "your" colour paired with a creamy/white extended leather interior and I almost caved in and go for it, rather than getting an M.
I just realised why I assumed it was an M, it's your wheels!
I am trying to think how my M would look, it I were to get a place to wrap it in the same colour as it shows with your sig. I use to own a Fender Strat Plus Deluxe guitar that was the very same colour. It looks great on both cars and guitars!