I would wait for the m3 four door. The M5 is very expensive but if you can do it then do it. I would rather not live with my parent and drive a 335i then live with them and drive an M5. Thats just me though and you need to be happy so good luck with the decision.
2010 AW e90 328i: 6 speed, Black Leather, Dark Wood trim, ZPP, ZCW, ZVP,ZSP, Nav, Xenon
BMW Performance CF Rear spolier and Gloss black grills
2008 Candy White MKV GTI 2.0T 6 Speed Manul Gone
2008 AW X3 3.0si: 6 speed Returned
2006 AW e90 330i: 6 speed Dinan Stage 1 Returned