Underneath, there's a single exhaust running to the back, which then enters a single muffler that, on the later prototypes, has four outlets. The production car will have four. The suspension links are aluminum and look curiously like the ones you'd see on a current M3. So do the enormous, cross-drilled rotors and the big black calipers hiding behind the gorgeous wheels. Remembering that the 1-series shares its basic design with the 3-series, strapping M3-like goodies onto a 1-series wouldn't be much of a stretch.
If you don't notice the big, finned rear differential when you're looking at the car, you will the second you drive the car.
But what you'll notice first? It has three pedals and a stick. Thank the Lord Baby Jesus, praise Allah, and/or send money to your local televangelist -- the Germans have finally gotten the message that those twin-clutch transmissions, awesome they may be, aren't a substitute for a row-it-yourself stick.
The shifter's throws are super-short, slightly notchy and accompanied by substantial resistance, just like they're supposed to be. The clutch takeup is perfect (just like in every other BMW), and the in-line six makes pretty noises from idle to redline. No surprise there. None of the prototypes wore a final-production exhaust system, and they were all quieter than, say, a 335is, but I spent a half-hour begging for more sound while a grinning German engineer told me to be patient. "Throw a microphone in the damn intake tract and a speaker under the dash if you can't get it to pass drive-by regulations," I whined. "Anything for more of that music -- intake, exhaust, whatever.."
Apparently in-line six noise is a drug and I'm a junkie. I own it; I'm fine with it.