I got a used '6 back in Sept. Have ran it a lot recently, beat the crap out of it. Took it to Psyco this year and ran at our new track (S&B RC Raceway). This thing has been a rock. I've had two issues.
1. Screws in rear diff loosend and lost all fluid. Didn't seem to hurt the gears.
2. Last race runs great until I refuel then will die. Even after reving it and clearing it before putting back on track. In last week's b-main - died right at start, pit man got it started back up but it put me in 10th. Worked my way up to 5th, came in for fuel then died, got it back to pits, started, died back on track. Wasn't too hot and was running like a champ until then.