skeets,
I recently bought a D55 online, without any real problems. Yes I had to dress down the frets when I recieved it, as it was re-fretted at some point and they put in like really high frets for some strange reason.
I guess from playing my D6 I kinda "knew" how this would sound and was able to take the plunge without any worries.
Maybe there is someone on LTG that is near to you, or you can find a shop that at least has a few Guilds so you can get some idea of sound.
If you have your wits about you, and LTG lookin' over your shoulder, you should consider ebay for sure. It's definitely "safer" than craiglist and likely cheaper than an actual store in most cases. Using Paypal - they do not release funds until you get the merch and are happy with it. The "best" of course is to buy direct from someone here.
As to the Guild for you in that range - I've only had direct experience with two ends of the spectrum so to speak - my D6 and the D55. The D6 is a hog and has a great tone, slightly muted perhaps compared to the rosewood dreads, but you can certainly spark it up by putting something like Tusq bridge pins in it.
If you have $900 to spare you can do better than a D6 for sure - but I have not played any of the inbetween myself. I do know that the folks here on LTG can be trusted implicitly.
One of the biggest helps to me has been this mash site that pulls all info from craigs and ebay into one handy format for searching.
http://www.jaxed.com/cgi-bin/mash.cgi?itm=guild&cat=mus