Hi, to add to this, there are actually two Intrax price options from Intrax / Alfa9.I personally would choose between novitec (being an affordable option) or intrax if money where no concern,
The first is the XL, and the cost is higher. This gives the stiffest rear unit possible at 52mm!
The second is the 1K2, which uses an upside down rear MacPherson unit with a very stout 45mm insert tube. This one is much more affordable than the full race XL and offers nearly all of the same benefits as the XL. Simple 1-way adjustability makes it suitable to anyone and gives easy adjustment for street or track use.