Both are going to be amazing!! M3 is more Race tuned and the G30 M550i xDrive more Street tuned.
The F80 is a complete M car and has the decades of race heritage behind it plus instant respect from those that notice what it is. The new Competition Package is very nice.
The strong points on the G30 include the latest Tech, xDrive and more room.
So much to say about both of these cars. I like the 4 door sports car theme that BMW does so well! Don't forget the new M5 will now have a version of xDrive!!!
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2011 E90 335i xDrive 6AT Performance Edition Package, M-Sport, TTFS Tune, VRSF 3.5" Catted DP, Active Autowerke CP, Turner Motorsport Strut Tower Brace, Hawk HP+, Bilstein B6, Alpina B3 TCU Flash, K&N ----
2014 F15 X5 xDrive50i M-Sport, RSE, 3rd Row