i think the 7100 would be plenty, but id probably get the 755. more versatility if you get inefficient speakers, more power if you need it, etc. you can always add on two m200s for 7.1 if you need to and it would only cost 100 more than the 770.

under normal listening levels the 7100 would have plenty of "headroom", because eventhough it has less rms, it still has adequate ability to go over its rms for peaks (i.e. into what is described as "headroom" without clipping). the difference is when that change occurs, at 100wts or 200wts? i doubt you have ever listened to (at home) 100wts of clean/pure power, as it is very loud. 200 is always better than 100 though, 2x better even, for not twice the price... just less channels...

good luck

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