Average consumption on my E92 M3 DCT is between 14-15l/100km with about 70% normal driving and 30% more aggressive.
The car is a great all rounder, I went from a 4 door E90 M3 LCI to an X5M monster, then back to an E92 M3, and still enjoy driving the car.
I have not had many issues with my car, but I am just over 30000km/s, so time will tell.
It does suffer at the reef against boosted cars with more torque, but I have never owned a more sure-footed car whether driving through a corner, in a straight lines, or sideways, I always know where its taking me and when it will let up. Its very forgiving, had many guys scream when going into corners, and the car didn't slip or slide, am sure other owners will bear testament to this.
Driving to the coast I get between 10-12l/100km with speeds between 120-150, on the way back its more like 10.5 -13l/100km.
For me M3 DCT with M-Dynamic, FTW, cannot drive a manual here in JHB with traffic.