Some good advice. Yes go for the beefiest you can find, even if the specifications can be spurious. As was said, the power supply is the part that matters, and its true specifications are often a closely guarded secret. This is not for nothing: it, and the case, are often the most expensive components.
In AV receivers, they are often on the small side given the number of channels that have to be served.
A crude proxy indication would be the weight of a unit, since good power supplies are heavy.
Don't even try to audition this stuff. The sonic differences will be tiny at best and discerning them will need a very careful setup with precisely matched levels and near instantaneous swtiching. This has to be done to within 0.2 dB, and that needs a rather good Volt meter at the speaker outputs.
Fortunately there are lots of good offerings, so enjoy the music.
Don't even try to audition this stuff. The sonic differences will be tiny at best and discerning them will need a very careful setup with precisely matched levels and near instantaneous swtiching. This has to be done to within 0.2 dB, and that needs a rather good Volt meter at the speaker outputs.
Fortunately there are lots of good offerings, so enjoy the music.