Get the M3 sedan with DCT transmission. Wife loves driving it, kids love it & so do I. Theirs lots of room for two baby seats in the back & the sedan makes it easier to get them in & out. When the car is empty & its just me & and an open road I have so much fun with the car. E90 M3 is the best all around & would never trade it for anything. Its 2011 so all the issues have been sorted out.
Also, that V8 engine is amazing. I believe allot of people will not like the new M3/M4 engine.