Steve,
The only possible downside to the Stebro bypass is the diameter of the pipe; it appears to be materially smaller than the Fabspeed.
There was a good post where the two were compared and the Stebro is definitely smaller, but I don't have I.D./O.D. specs. Can't remember if the post was here or on
www.renntech.org.
FWIW, I have the Fabspeed pipes and vouch for their size and quality.