It comes down to whether or not you plan to keep the car for a long time (5+ years).
I like the idea of a beater. You can run it up on curbs, park 2" from another car when required, and you can teach your wife how to drive stick on it without worrying about a $1K+ clutch job.
2013 F30 328i Melbourne Red
2011 E90 M3 Monte Carlo Blue
2004 E46 M3 Imola Red