I was thinking of buying the 755 to run my 5-channel HT. However, all of my speakers are biampable. So, I'm considering buying the 770 for two reasons: (1) it's a future upgrade path to 6-7 channels; and (2) I can biamp the front R/L speakers or the center channel speaker.

Has anyone biamped (by biamp, I mean split the signal coming from the preamp, route it to two amps on the 770, and run wires from the amps to the two inputs on a speaker) their speakers with the 770?