The current M135i is an overall impressive proposition. I guess that BMW is anticipating on increased taxations worldwide. Every bit of CO2 will be punished badly and buyer will bleed money on having committed this sin. Only then the 2l/4cyl makes sense, and also only when consumption is down by a clear stretch. How they'll do that is a mystery to me actually?
Nor the Audi S3 nor the AMG A45 are on par with the M135i...they are only slightly more efficient, and sacrifice the smoothness of the inline 6 which is omnipresent in the M135i.
When BMW is going that road, I can only hope they pull some tricks out of their sleeves...