For all Asian Fit Goggles from Oakley, the only difference is the nose padding. If you compare a std and an asian fit version, look at the foam around the nose. You'll see that the Asian fit's foam is a lot thicker. It basically fills the gap created from the lack of a bridge. The good thing is that all the lenses are interchangable between the reg and asian fit goggles of the same series.
As for the Spy's, my wife had the Spy Comet's and they did a pretty good job of sealing up around the nose. She prefers her Stockholms though...