There has been some discussion on these before, with some people saying rear-mounted turbo systems are terrible, some saying they are wonderful, blah blah...
The theory is that a rear-mounted option decreases installation cost and removes the ambient heat generation of the engine bay. They offer a kit for the non-NR motor 350Z, and I believe it is a single turbo solution.
One thing is for sure, they sound sick as hell with the turbo replacing the muffler
Edit: Also worth noting, as long as you size the piping right, long intake tracts shouldn't be that big of a deal.