i am running:
-trinity 3300 cells (not pictured)
-trinity monster stock motor (p2k in picture, not that u can really tell w/ the heatsink on)
-Novak Atom ESC
-Hitec servo, HS-625MG
-Hitec FM lynx and dual convesion esc, soon gonna upgrade to Lynx 3d

the TC3 started out as a Racer kit, but its upgrades include:
-graphite chasis and braces
-Graphite shocktowers
-Graphite A-arms
-the ligthened diffs
-those blue collar things that go in the hubs, forget what they are called, but they help u tighten the wheel w/o making it bind.
-Steering rack bearings (the bushings develop slop after a while)
-RPM ball cups
and thats about it...

as for the gearing, i run the stock spur, 72t i believe, and then run anywhere from a 26 to a 30t pinion. But i havent raced my new motor yet, only practiced at a track thats much tigheter than usual, so I dont really know where my gearing will be. With the P2k i used a 30t pinion usually, and if the track was tighter i'd drop a tooth or so, and if it was really tight like where i practice at, then i'd lower more sometimes. However, the monster stock says to run about 2 teeth lower than most, and the p2k said 2 teeth higher than most, so i started out running a 26t, and it seemed good, this was on a very tight track, i'll probably move up to 27 or so for the actual race on a track thats more open. Btw, the suggested is 28 for stock. With a 7 turn the manuals suggested doesnt go that low does it? go to rc10.com and on their board ask if u cant find a suggested gearing chart that goes down that low. I think they changed the board to say its the T4 one, but they still answer questions on all of their kits. Hope that helped some.