That test looks substantially better than the others, I think you're on the money with the settings you used to create that.

With those vegas settings, they're almost exactly the same as mine, though on this tab http://img204.imageshack.us/img204/5649/swscantif.png i dont have mine set to 100 Video Smoothness, i have mine around 80, but that wouldnt cause you to lose quality, infact it should be better than mine

Maybe do a playtest now and see how the resulting vid comes out.