There's one point that everybody has been forgetting, or they're unaware-of, so far...
There is another advantage to using monobloc amplifiers, if they are located appropriately. With a multi-channel amp, some people are running long lengths of speaker cable, perhaps of questionable quality, to save money. Long runs of speaker cable result in signal loss, vulnerability to RF interference and compromised sound. It's better to run a long SHIELDED interconnect to an amp located right beside the speaker, and a short high quality speaker cable to the speaker.
Of course, this kind of set-up is not for everybody, but there are definite advantages!
There is another advantage to using monobloc amplifiers, if they are located appropriately. With a multi-channel amp, some people are running long lengths of speaker cable, perhaps of questionable quality, to save money. Long runs of speaker cable result in signal loss, vulnerability to RF interference and compromised sound. It's better to run a long SHIELDED interconnect to an amp located right beside the speaker, and a short high quality speaker cable to the speaker.
Of course, this kind of set-up is not for everybody, but there are definite advantages!