Tony Kart Differences Racer, 401 and 401s

Looking for some info on the difference on some Tony kart chassis.

I came across some old stock rolling chassis at very aggressive price brand new Tony Kart Racer

Is their a big performance difference between the older Racer chassis versus 401/401s



The 401 is 2015-2016
The 401s is 2017-2018.
The 401R is 2019-2020.

From the 401 to 401s there wasn’t alot of changes made to the chassis and equipment is very similar. Speed was similar as well.
The 401R was the first model with some noticeable differences.