For one, i believe the 70RR has been replaced and re-designed...
J's Racing - FX PRO Titanium Exhaust
http://www.jdmconcept.com.au/part/js...egra-dc5-01-07

If your thinking about buying the one that's on ClubITR and has a flange that's broken... I think you'd be making a mistake and i think you putting this exhaust system on a street car would be purely pointless....
It's Titanium, not stainless steel... Very different product, a very expensive product....

Buy a 60RS, save yourself the headaches.