Thanks everyone for your input. Again, I change cars often and am just looking for opinions really on how competitive on the track an m3 will be in comparison to cars like the SLS, GT3, California, etc. Not trying to brag. Just looking for honest feedback. Maybe i'm just looking for a few fine folks here to convince me to get the m3 or m4 over the others.
That said, the GT3 is nice. I think i've ruled out the GTR and x6 M.
My list in order:
2. Porsche GT3
3. SLS AMG
4. Aston Martin v12