Sorry, we are no help.
If the bigger cars are any indication:
Sedan, coupe, cab... (wagon?).
Of course there is a lot more brand recognition for a 2-door M3. Anyone remember what happened with the e36 M3s?
Now that I think about it, I don't see how they couldn't come out with the coupe first. It would be a huge disappointment for enthusiasts in any other order.
Of course this is all speculation on my part.
Tine and Speedfreak always have massive opinions on this sort of stuff. PM them a link.
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