I run a single Hitec HS-645 steering servo right now, its not the fastest servo, but it does its job. Its only temporary, my futaba pooped out on me a hobbytown so i just got this one. I'll get something better when i have my Spektrum. I hope my revo is highly competetive. I run 40 series bowties. I'll definately be racing during the winter too.
-Pete