From what I could gather at the time, the OS needed more load to really shine. The Thorjet with the added blades gives you that load. The K&B 48 or 7.5 seems to shine using the Turbax. I'm sure the OS will work fine in the Turbax, just be careful not to over rev it or it won't last very long.

Do a search of the archives, you may find some more user stories. I remember a bunch of talk about the VX's losing power after a gallon or so. This is not to say they are useless at this point, just less powerful than new. Peter is the one person who seems to have had very good luck. Maybe he can measure the pipe length and let you know his break-in process, fuel, plug , etc..

Mark