After about 10 packs of running, the new damper part seems already solved the common problem of SSBB damper. That is, the membrane will sometimes drop into the cylinder after bump. The alum retainer is snug with the new ball end so i will pull the retainer towards the ball end to make sure that it had completely sit on the ball end.

The new adjustable arm is only benefit for the player who is well- known to the suspension theory of RC car. For me I only change the rear toe from 2 to 3 degree depend on the track layout so directly change the rear mount is faster than looking at those stupid bushing. I am more interested on the new rear hub.