I'm running an older Novak SS 17.5 that I paid $20 for with a 2-year old Novak GTB. It's the car to beat here, but our track is a bit smaller than average. I'm sure that on a larger track my friend's Tekin-powered TC5 would gain some ground on it, but then again I haven't even messed with timing and my gearing is somewhat conservative. Always comes off lukewarm at best.
Wow, this post really didn't help at all, did it
Now that I think about it, I used the Novaks at a larger track up north and it didn't have any problems keeping up with the others.
Basically what I'm saying is, for the price you can't beat a gently used Novak.