I like Orbx airports, they are some of the best. So far though, I haven't really found their other scenery very good but I've only used the (2) free scenery packs (Tasmania and the PWN one). For the PNW one, I mean it's using textures that look just like the default textures.
Tileproxy is the best but only if you can cache it all first for your flight, TileProxy also seems to have a very poor caching algorithm (something wrong with it), as the results are very inconsistent I'm noticing from one flight to the next. Tileproxy does not seem to be able to re-load an area at the highest resolution, even if you already visited it at a high res (that's what is odd).
The first couple days of my TileProxy experience I was getting ultra-high quality tiles that looked good, but now it's loading a lot slower. I don't know why, but I think unfortunately it might be the mapping services throttling bandwidth when they detect heavy usage over a given period of time. I don't think it's the PC or files, the difference is too large from before, besides files don't fragment much in Win 7 like they did on older OS's.