Best thing to do is tear down the kit and rebuild to what is called for in the factory manual. Then go to you local hobby shop and get a copy of the XXX Main Radio Control Car Chassis Setup Guide. That will help you learn just about all you need to know about setup based on what the car is doing on any given track. Hope this helps.
I've seen every kit out there and if the setup is right any of the kits mentioned can take you to the front of the field. You just need to make a commitment to learn how all the different adjustments can effect your car.
Regards,
Speyederjedi