the 6600 is really the new version of the 6900---not the 7000 which is more powerful than both. in fact, the 6600 has the new volume control (optically controlled analog if i'm not mistaken used in the C2300). it does not have the 5 band tone controls though---you have to go to the 7000 if you want that. on the flip side, it has an 800 HD tuner card that is supposed wonderful. the 7000 does not have the new volume control, curiously enough.
the 6600 also has better build quality than the 6900 (knobs, posts on back, LED lighting etc). i personally would either go 6600 or 7000 if you need more power.
the 6600 also has better build quality than the 6900 (knobs, posts on back, LED lighting etc). i personally would either go 6600 or 7000 if you need more power.