The truth is, I'd rather play a plug-in that used graphics I know are good, rather than be forced to settle for graphics that are original, yet low quality. The general consensus is that missions make the plug-in, and I agree. If you can make kick-ass graphics, I'm all for it, but if not, use some of the excellent free graphics on the web. And there are a lot of free sprites and such out their.
A word of caution, though. While I enjoy good graphics, I find that I like consistency even more. I hate it when there are some ships that look really fantastic, and five minutes later you see one that looks terrible.(Kind of like that death ray mounted bulk freighter.) If you're going to use other people's graphics, make sure that they fit in with the other graphics at least to a degree.
Of course, that's just my opinion, I could be wrong.
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Every (url="http://"http://www.dropbear.trav.net")drop bear(/url) I see drives me closer to the edge