My first outing with the TRF421 ended with a broken ball nut that holds the lower suspension arm. It was a hard-ish side swipe, the arm didn't break (TRF421X arms) instead the ball head broke. Local store don't carry that (as most other brands are 6mm or 6.5mm).
Anyway, I'll be swapping out the lower arms with the Schumacher-hardware CF arms with new set of ball nuts.

When it works, it's a vey very stable car and easy to drive.