Sound samples, eh?
I have a basic dual source setup, B-band, installed in a Taylor jumbo on my kitchen table. There's an electret undersaddle pickup (NOT a piezo - completely different design) and an internal condenser on a small gooseneck mounted on a clip (read "strong clip") to an x-brace. Both circuits plug into a Core 99 preamp installed as part of a twin line endplug jack. The unit is powered by a 9 v battery housed in an aluminum clip velcroed to a patch on the side of the neckblock where I can get to it by loosening the strings. Wiring clips are installed on the top kerfing at regular intervals.
The only invasion to the guitar was drilling out the endpin and replacing it with the endpin jack (if you do this yourself use a drill press or at the very least, a brad point drill bit, very, very sharp, and hold or clamp a wooden block tight to the inside surface of the endblock to eliminate the possibility of splitting) and drilling a small hole through the top underneath the bass side of the saddle to allow the ribbon transducer to go into the guitar. Don't allow anything (wires and such) to touch the ribbon transducer or you will get booms - the entire thing is a real mic.
B-band has improved the line since I bought mine, but they're still pretty inexpensive for what you get. You can easily set the unit up to run on phantom power now, for instance. B-band also has a hell of a nice external preamp that replaces the internal circuitry.
I realize this isn't the mp.3 forum, but you did ask. Here are a couple of tunes I did (please excuse the newbie production quality - I was exploring things like "echo") with just the guitar plugged directly into a Mackie CFX mixer (the preamps are not as good as the VLZ series), two channels, one for each signal, and running tape outs (R & L) to the line in of my Soundblaster card, into n-track. EQ is basically flat with a bass roll off. Pretty newbie setup.
Walking in Jerusalem has the least junk done to the guitar signal. Pretty clean; Reverb is a little intense.
Sitting On Top Of The World has just a bit of reverb on the guitar.
Red Haired Boy was overdubbed with a second part, and I experimented with all manner of plug-ins. Too much pepper in the sauce, I'm afraid. Gonna have to do that over again.
www.nowhereradio.com/treeline Go to "Discography."
Since these were done, I've scored a Presonus AcoustiQ preamp, so the sound can now be EQ'd relatively easily on the fly.