Well I have been corresponding with R2C for quite a few months now on the redesign of the single 350z/g35 intake. They have discontinued use of the plastic "square tube" and designed a round aluminum tube. While there for some dyno sessions, the round tube produced 10whp more on the dyno vs the old. Even the engineers were a bit baffled, but the numbers are what they are. I'm still awaiting for the arrival of my tube and can't wait. The intakes have been officially released and ready for immediate purchase. Available in polished finish and also the best option in my opinion, black nickel. Black powder will be available in the near future.
Run# 1 & 2 are round aluminum tube and run# 3 is the plastic square tube. The difference could also be felt from the drive back to the shop from the dyno.
I am still trying to get them to work out a price for just the tube for those that already have the intake and want to upgrade.