A couple of things. The 2012 M Sport Package came standard with 19" 233 rims:
http://euroactiveparts.com/images/223%20Wheels.jpg
The 20" were an option - on the M Sport option.
Also, the M Performance package which is the equivalent of a mild stage 1 tune is only available on the 2013. I bought a BMS Stage 1 for $350 and love it.
That's all. Carry on.