A lot of good systems out there to choose from. Tekin, Hobbywing, Viper, etc. I would recommend something in the 10.5-13.5 range with an esc that can ramp timing. You can run it with no timing until you get used to it and boost it later for more speed. I've ran 6.5, 8.5, 10.5 and 13.5 in sc and was most consistent with a 10.5 and 13.5. Races aren't won on the straight especially in sc where ease of laying down power is important.
http://www.hobbypartz.com/07e-10-5t-...n-60a-led.html
I run this esc in my 4x4 short course with a pro 4 4600 and it works awesome. You can change the firmware to allow ramping and turbo.