I ran my Zero S for the second time this last Saturday in our local club 17.5 (Blinky) class. I qualified last for the A-Main, but managed to move my way up and finish a very solid 3rd. I was one lap up on 4th, but two laps down from the leaders. (9.5 to 10.5 avg fast laps in A-main) I felt this was a great result since the top two guys are definitely veteran racers with years of experience and I've only been racing TC's off and on for about 2 years.
At the club level, this chassis is definitely more than capable. The stock set up is pretty decent for carpet. I moved my front shocks in one hole and the rear shocks out to free up the back end a little and to gain more steering on our very tight track. I also added about 2 oz. of weight to the battery side to balance things out. I might reduce that a little though.
One thing I don't like is the rear droop situation. It seems the rear shocks are too short to let the rear arms drop down in the proper range. I might switch out to a longer shock end to help out with this. The fronts are okay though. I also need to find a slightly thinner shock spacer. I go from 6.5mm to 4mm ride height with the stock stuff. I need to be at 5. Maybe new shocks and the +4mm towers are my next upgrade?