Why would they? They're not coupes, despite what ridiculous name the manufacturers use for their "niche".
My thoughts exactly. I can't wait until this stupid "4-Door Coupe" fad becomes passe. These are simply SEDANS with low rooflines, limited headroom, and frameless windows, NOT Coupes!
As for these 3, I'm oddly underwhelmed by all of them. I'd be much more optimistic about a debate/poll about the more "normal" E/5/A6, or 7/S/A8. Even though this segment is supposed to be purely "passion", these cars just look somewhat confused to me. Halfway gorgeous and halfway flawed.
All these cars have tons of beauty to them, and all have their perks which are well documented, so I'll state my cons:
CLS: Messy design, nonsensical lines and lacks the effortless grace of the others, or its forefather. I can't fully get on board. It did however invent this "Segment", and it'll always have that to tout. I think that it's both the most stunning/striking and hideous of the 3 ("hideous" is a purposeful exaggeration to get the point across), also, it's the most unique.
A7: Nice, simple, however, lacks a bit of flavor to me, and the rear is a total dealbreaker.
6 GC: Looks like BMW didn't put much passion into it, you can see the Marketing/Boardroom meeting to "get this out there to get some Market Share in this growing segment" written all over the car IMO. Nice, and maybe the most cohesive of the 3 (certainly more than the CLS), but doesn't inspire me or make me want to spend money on it.
I guess since I don't have a favorite amongst these cars, I can't really put my Vote in yet. However, I will say this: If I had to buy any of these, the ONLY one I could is the 6GC, as the CLS let me down by not even giving me a chance to fall in love with it and want it, due to the TERRIBLE USE OF SPACE by M-B engineers. It's a huge car but has as much Frontal Headroom as a Ferrari 360 Modena. It actually has LESS Frontal Headroom than a VW CC, how is that?? The A7 also is too cramped for me up front (I'm 6'4).
Judging by the GC's dimensions chart, it looks like it has very generous Frontal Headroom, so it's the only car that I can truly have. So, I guess, due to BMW's engineers beating out M-B's engineers in the functional department, and thinking of us "tall people" (I'm about the average NBA Point Guards height.... M-B can't make a 4,000 lb, large 4-Door accommodate me?), I should go Vote for the BMW....