All good points here. I'll toss another idea into the mix. With the arrival of the Model 200, you could get a 755 now and when/if you decide to go to 6.1 or 7.1 you could get one or two Model 200's to add to the mix. It will take more rack space (as alphanstein noted, the 770 crams two extra channels into the same cabinet as the 755), but will cost approximately the same (maybe $100 more with shipping). As for whether the extra channel(s) is worth it, I have been very pleased with my 6.1 arrangement.

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