Last night I ran the 4XS on a high grip outdoor, astroturf track for the first time in a couple months. From the very first lap it felt incredibly fast and nimble, without having the negative characteristics associated with too much traction. It didn't have a tendency to traction roll at all, which meant I could push it harder and harder and the car would just take it. The reward was faster lap times every time, and managed to set the track record.

With the new CNC machines diff crown and pinion gears, the drivetrain is now very quiet and bulletproof no matter what track you run on.

With the appropriate setups, this car has been very fast and consistent on a low grip, outdoor bumpy clay track, and now on a high grip, smooth astroturf track. This proves that the car can be setup to be very fast, yet easy to drive in any track conditions. This car is an absolute masterpiece.

A lot of xray parts? Can you tell more about that?
Sure, when using the aluminium rear hubs the rear axles tended to break quite easily (although I believe the material may have been updated now to be less brittle). For a short term solution I tried to see if axles from a different manufacturer fit, and the Xray XB4 axles fit perfectly. You just have to use the Xray CVD collars, wheel pins and hexes to make it work. So far I have had good success with them, without any breakages.

I saw some others try the Xray XB4 9 degree castor blocks, and thought I would give it a try because I have always been looking for a bit more steering and nimbleness out of the car. When I tried them it unlocked more steering, and it also opens up scope for front wheelbase and roll centre adjustment. I believe now Thumbs Designs make optional castor blocks designed for the 4XS, with 7 and 10 degree options.