Well, that's a hard choice for me. On first thoughts I would
fcourse the E92M3. More power, NA engine (no turbo shit etc.), more sportscar. On the track the M3 wil be the faster car.
BUT,
The looks are very promissing of the 1M. Wait until I can see it in real live, but I do like the styling of the 1M a lot. More then the M3. And ofcourse the 1M will be also a very fine car to drive, and a lot less money(!) and for daily use also very good to use.
So, I think I would give away the better drivers car (E92M3) and take the better looking car (1M) in stead. The 1M is good enough. Maybe some better 'pure' image to. And thats what BMW M is all about.
Note: I do agree of some members here. If you truly want a sportcar, go Porsche. Take the Spyder! I have driven it. So much better as a sportscar than BMW nowadays.. no doubts.