i'm talking about the japanese av amps which are popular on these forums, not higher end kit like Linn/TAG etc.
c'mon man that should have been obvious

Obvious that everyone follows the heard and doesn't look for any different, then complains the 2 channel performance is not so hot.... you get what you pay for !!!....
Buy a box that does everything for 500 notes, video upsampling, DAC, multi channel, power amps, fancy room EQ....etc etc etc... take out the cost of the box and shipping and you have about 20 quids worth of analogue amp left, too many corners have to be cut to make it....
Crazy thing is people think it's ok for 3.5k on a big screen and cut corners on the audio, or think it's "high end" if it's more than a grand....
When all you do with a big screen is watch a movie, you don't need 60 inches for the news !!! But the audio side is used for movies, music, ie much more of the time. So you get better value and use for your money.
Anyway my "High end" Linn Pre, around 4.5K new, cost me 2.3K second hand, which is still over 1K cheaper than the Pio 600A, more than enough for a S/H Linn 5 channel power amp...... Let me tell you, "stereo" performance is NOT compromised.
But then I use my system 90% of the time for music. Just depends on your priority, but no there is no technical reason why an AV amp can't sound just as good.