The difference is not hubs, spokes or necessarily build. It is, as already mentioned, all about the heat behavior of the rims. Nick, I suspect (just an observation, no offense intended) you still think that there is some magic in wheel building. I assure you many folks do as well at home as Zipp on the build and there is no reason why a Chinese factory can't asssemble wheels as well as possible. And good hubs and spokes are readily available. But the rub is in the rims.
Last edited by rpenmanparker; 05-30-13 at 03:19 PM.