Well the new Turbocharged 4 is just a hell of an engine. I drive a 2011 335i and I took my car for service a few weeks ago. They gave me a 2013 328i (with the new turbo-4) and I was thoroughly impressed; so much so that I didn't miss my car at all. It was zippy, responsive, had great torque. The 328's I'd driven before (with the I6) always felt lethargic, very "rental-car" ish. I don't think I'd be happy driving it, but if you don't really drive fast or spiritedly, you might not mind.
With the 135 I think you'd have a blast. Gets good gas mileage too.