It will depend on the gearing I think. The 6-speed might make an extra gearchange up and down if second gear doesn't make 60 mph. Otherwise, narrow track, short wheelbase, sorted suspension from the factory and good power sound like a nice stock class autocross car. I know it would be fun to try one. I have driven a stock Focus ZX3 on a autocross and I will say it would be tippy in a novice's hands. The lowered suspension on the SVT version will be a great improvement.
I also noticed in Fastrack that slotted/crossdrilled rotors of stock size will are being considered for approval in Street Prepared. That way I won't have to run my n/a Miata in SM2.
Respectfully,
Andy Hohl