everyone pretty much touched up on the necessary hopups. I wanted to add to that with the aluminum propeller shafts. especially the rear, these are much lighter than the stock cast ones. The main weapon of the TB03 is the free drive train over belt cars. reducing the rotational weight (about 10g I think) of the drivetrain will add to that advantage.
I am very satisfied with the car and running head to head with xrays, 415, RDXphi, etc.
But I have to admit that I am such a sucker that my car doesn't really look stock anymore. Looks like I went to the future and picked up a TB03-R
Ah, the Tamiya magic.