You can't judge a car by how it finishes at pro races. The drivers in the "D" mains are just as fast as the "A" too often. Thats racing. At that level some luck is involved.
And howmany people that judge a car by pro races even make the "F" main anyway???
Is a "b" main finish at a big pro race really a deal breaker? It shouldn't be.
As for parts....most pro's are running off the shelf hopups available to anyone. Not like the old days where every car out there was unobtanium. Some guys do have to run some stockish cars for R&D purposes.
The fast truggies I've seen:
HB D8t, Xray XT8 (old fashioned handleing), Mugen 6t, Losi 8t.
There is something about the D8t. Good rotation like a Losi, but it feels heavy and planted. Good shocks. Cheap CVD's. The truck just works.