Eh, probably not a good idea unless you clean out the piping.. they're all carbon coated inside..
PVC works great as long as you take the finished product before you install it, and get some exhaust tubing that has the same OD as the PVC's ID, and press it in the inside of the PVC pipe.
That will make it more stable under heat where the clamps are placed, as it's braced on the inside to protect against collapsing.
I just don't like the look of it.. it's too ghetto.
If you do it right, well, you're not technically doing it "right" using PVC, but if you route it right, you won't see any of the pipe connections and people won't know it's PVC until you tell them.