Space gray but only because I like darker colors. Mine is Black sahpire, and it is true as most pointed out it hides 335IS details.
If you go with SG, get two tone light interior. Black interior will get old soon! Mine is Oyster/Balck, and it really brightens up the interior.
With AW Brown/Black interior looks incredible..
2016 F80 M3 BSM with Black interior DCT/Driver Assistance/Executive/LEDs/Adaptive/Black Wheels
2014 F32 435i xDrive AW/CR
2014 F25 X3 M-Sport Carbon Black
2011 e92 335is 2007 X3 122k miles 2006 e90 330i 132k miles