My wife's 335is Coupe is Le Mans Blue, an exclusive color for that model. I don't see that as making it any less exclusive for the E9x M3.
Interlagos Blue was offered both on the Z4 M and the E46 M3.
It's a few years away, but I'm planning on Estoril Blue II for my M4.
His: 2016 M4 Coupe | Sakhir Orange | Black Full Merino | CF Trim | M DCT | More | ED 5/13/16
Hers: 2011 335is Coupe | Le Mans Blue | Black Dakota Leather | Dark Glacier Aluminum | 6MT | ED 5/12/11
Also His: 2006 Z4 Roadster | Interlagos Blue | Black Extended Nappa Leather | Carbon Leather Trim | Purchased 7/19/12