CLA 250 it will be the rival of 228i as A250 is the rival of 125i.
S3 offers close performances to M135 / 235i.
CLA 45 will be on par with RS3 and M2.
In this moment Audi doesn't offer an engine for A3 with ~210 / ~220hp, but they could use a version of the one found in the new Golf VII GTI.
Also MB doesn't offer an engine between A250 and A45.
So let's have a clear look at least at the engine choices, because for the US market Audi will offer a sedan (A3), MB offers a gran coupe and BMW will start with a coupe
