BuellerPilot, as far as the undertail goes, the visible part looks fantastic. The backside looks pretty rough. I think the Chinese ebay parts are one layer carbon fiber, two layers fiberglass. And the backside is just plain unfinished fiberglass. I still haven't installed it, so I don't know what the fit is gonna be like.
Also, may I recommend that when you purchase your carbon fiber stuff, stick completely with the same vendor. If you want to do it right (and expensively), go Buell OEM. If you want to make every possible part of your bike carbon fiber, and do it cheaply, go with Chinese ebay parts. And if you want some happy medium in between find a quality aftermarket supplier like ASB.
The reason I have the Buell part for sale is because it doesn't match the weave of my new Chinese undertray piece.