This is a great idea and has a lot of potential. I totally agree with bimmerjph that the belt line is too high. My biggest criticism is that the facia needs the grill like the '70's cars. This has way too much "body" on the face, almost like a rear engine car (Karman Ghia, Corvair). It makes it look tall and blunt as opposed to wide and low like the original. The CS is my favorite vintage BMW and I'd love to see a modern interpretation of one. This is a good start but needs some tweaking.
2013 328i M Sport