I am thinking of buying this kit for my 400 Scrambler.Any input would b appreciated.

 

I think you'd be better of with a HPD trail set-up. Main difference is that HPD has a better pipe design, head desing, and the 39PWK carb is easier to dail in.

RCR can set you up with a great kit as well, and probably for less that either of the other two.

Modding these 400's isn't as easy as it seems. With the clutch tuning that goes into them so much depends on your particular riding style and intended use of the machine.