Speaker cable for 25' run flat/small for under carpet ??

I would like to change my room configuration so that I can sit further away from my speakers. This will necessitate changing out my 8' pair of Audioquest-8 bi-wires (8' long). I'll need to run them under carpeting to hide them. I hope to find a bi-wire pair 25' long that are at least as good as the Audioquests. I'd consider any/all, new/used, but "good value" would be welcome. Associated equipment:

Cary CD-303 player
Sim Audio I-5 integrated
McIntosh MR-77 tuner
Tyler Acoustics Linbrook Monitors

Many thanks!
Look at any of the Nordost cables. They are excellent and flat. Perfect for your application. If you have any questions feel free to email me.
I second the Nordost. They offer wide cable for bi-wire applications, too.
Agree with Jtinn - Nordost is probably your best bet. Straightwire also makes an excellent flat cable, however. As always, try to audition them in your system before purchasing. In home trial seems to be pretty common with cables.
Try Audioquest F-18. On sale at AudioAdvisor for .97 a foot. Good cable and you can't beat the price.
Goertz Alphacore
Nordost can get very expensive in those lengths. I think their red dawn cable is quite good. A big advantage of nordost cables in general is that they don't seem to suck power like some cables. I find I use less gain with nordost verses other cables. A consideration since you are using a medium sized amplifier.

You might want to give analysis plus oval 9 cables a try. They are only 'somewhat' flat - maybe 3mm x 10mm. Very smooth sounding. Sumiko OCOS cables can sound very good in some systems too - very quick medium high detail level. Their advantage is that long lengths are relatively inexpensive. Another very good cable is the LAT. You can give the guys at www.echohifi.com a call. Very reasonably priced for the performance.