How about a multichannel amp drop? Most multi-channel amps intended for AV use quote their power in terms of two channel power... 150W! But if you're driving five channels... uh oh, now we're down to 70W or 80W. More troubling is the lack of headroom for peaks, which falls slightly faster than the RMS info. Same is true for AV receivers.
There ARE some excellent multi-channel amps that are designed around 5 to 7 channels all with equal power - and don't hide behind a two channel rating. Outlaw Audio has several. Parasound has a few. NAD has a couple. I'd love to see a drop for a good, powerful multi-channel amp.
I've got an AV amp rated 140W... two channels, driving my 5.1 system. Subs are powered. My front speakers are 92db efficient. I should be able to blow out my ear drums, right? Nope. My center and rears are also 90db... but that 140W/ch, once it's divvied up, just isn't enough. If you've got a receiver, you'd be blown away by how much difference it would make to use your pre-amp outs to a truly powerful amplifier.