The z4mc isn't going anywhere, but on lookout for a daily driver coupe, this is probably as rounded as you can get for a do all coupe, 4 proper seats, 50+mpg, 0-60 in 4.5s, the only drawback is waiting 2-3 years for depreciation to kick in before one can be had for reasonable money
http://www.alpina-automobiles.com/en/models-alpina/d4-biturbo/powertrain.html
http://www.alpina-automobiles.com/en/models-alpina/d4-biturbo/powertrain.html