As for me, since I have it, i only use the 2mm top deck with only 6 screws! This is the way the car works better for me using rubber tyres!
About the parts, I had not real problem since the beginning except with the shocks that i really dont like. Problem I had with them i that the collar doesnt fit very well on the body shock and it was almost impossible for to adjust it as i want.
i have run tamiya shocks on my car this weekend and the cars was definitely better