With standard visual cues that come only with the 128i's optional M Sport Package, the 135i has an aggressive front bumper with three large air inlets. Xenon headlights are standard, and they carry a white bordering up top for 2012, mirroring the headlight treatment across most other BMWs. These lights include a string of LEDs embedded in the caps, a visual cue used in the automaker's redesigned 6 Series.

Rather than the 3 Series convertible's folding metal hardtop, the 135i convertible has a fabric soft-top that can open or close in 22 seconds, BMW says. It operates at speeds up to 25 mph.

The 1 Series remains a small car overall, about 2 inches shorter and narrower than a Scion tC. The popular 3 Series coupe, in comparison, measures about 10 inches longer.