They had one at the Baltimore GP and I shamelessly climbed inside and poked around it. I'll withhold judgement on the interior because this (preproduction?) example had horrible fit &finish, but it might get better once they start cranking them out.
It looked sensational from certain angles and clumsy from others. It's huge of course and has amazing road presence. Not that I could afford one, but I really hope to drive one someday.
2004 Z4 3.0
2014 X1 28i ED
2015 F80 ED in June