Both the SC12 and SC14 have rotors made from extruded ally and are hollow in the middle, with a wall thickness of about 3-4mm plus the Teflon coating, so if you spin them to fast the rotors grow and the Teflon on the ends of the rotors wear off against the side of the body.
I have been there done that 15,000 rpm on an 18RG motor.
With the high boost if you have the SC14 on a 1300 cc motor it works Ok. But the higher the boost the harder the SC has to work and the less efficient it works,
So it is a compromise. If the engine runs a half decent compression around 8 to 1 it will perform very well on low to mid range boost.
I have a 4k that has 1ggte rods, forged Honda pistons in it, comp is at 8.5.
It runs well on 7 psi, but needs 98oct fuel to stop it pinging
I have just stripped the motor down to rebuild it into new shell and found it pinged to much as all the ring lands on the pistons are broken. But motor is 6 years old and driven very hard.