I got my M135xi last friday
Oh my god, it is such an awesome car and so well balanced, even with the xdrive! Almost no understeer but if you push it really hard, you can get it to oversteer, on dry, and even without being in sport+!!! Okey, we had like 0degrees C today and i am on summer tires...^_^
I am sooooo glad i went for the xi. Bmw really kept its promise; a 4wd with tendency to oversteer.
And the engine, the exhaust, and the adaptive suspension... Perfect!