First off, Welcome to the forums
I have SMG in my M3 and I LOVE IT! My father, who usually drives the car is always on the phone, that is why he got SMG in the first place, because it is sooo well rouned. However, i have never been in the new 6 or 5 with SMG in it. So I can't accurately tell you anything but that I love it in my 3er.
If you are not doing to much work, city driving, traffic driving I would definately go for the 3 pedal. It is just more fun...
Dinan Stg 2 Phoenix Yellow M3