I'm using UHD for all areas that it is available for - I just cut/pasted it from my XP10 install into my XP11 one. (I know, I could have used symbolic links..)
That is Charleston, WV airport in the screen above. Default - and by default I mean that someone obviously submitted a 3D airport to the X-Plane database and it is now included in the default scenery. I think I had read somewhere that up to 10% of the world airports now have WED created 3D scenery by users..which is a fair amount.
For those that don't know what that means - it just means that the default airport editor structures and objects library were used to make an airport more realistic. All the airports use the same default X-Plane object library..but the placement of the objects is custom by someone that submits it to the X-Plane Scenery Gateway. More custom airports use other libraries that are not X-Plane libraries...if any of that makes sense.