Thanks for your 2¢!
Still, there is the question of what power ratings should a shopper pay use when comparing different amps or receivers? Most or all AVRs sold in the US publish a list of different power ratings in their owner's manuals. At first look it can be bewildering because of all the different power ratings. I focus only on a power rating that includes words indicating that 2 channels are driven, a frequency range (20 to 20 kHz), a load of 8 ohms, and a defined level of total harmonic distortion (such as 0.08% THD). This rating may include the initials FTC in it. To compare the power of different AVRs or amps, I'd use only those ratings. I'd ignore any other rating type, such as DIN, when 1 channel is driven, when testing only at 1 kHz, or when THD levels higher than 0.1% are mentioned.
I'd also look only in the manufacturer's owner's manual for those specs. Other sources may mistakenly or intentionally get some part of these ratings wrong.
