A lot of recommendations without any concern for what speakers will be driven (and their sensitivity, impedance, & phase angles) and the preamp/dac that will do the driving (and whether there will be an impedance mismatch between it and the amp)...
Also, plenty of amps are up for sale because of upgrades. People do buy more expensive models from within the same family simply because they love the sound and want "more of it." And some people end up with speakers that don’t match amps they love. I had to sell my Coincident Frankenstein 300b monos for that reason. It’s a lot easier to move an amp than a pair of 300lb speakers. Finally, ears and systems work differently and something that would sound terrible in one situation can be another person/system’s dream amplifier... usually because of problems in speaker/preamp matching.
Also, plenty of amps are up for sale because of upgrades. People do buy more expensive models from within the same family simply because they love the sound and want "more of it." And some people end up with speakers that don’t match amps they love. I had to sell my Coincident Frankenstein 300b monos for that reason. It’s a lot easier to move an amp than a pair of 300lb speakers. Finally, ears and systems work differently and something that would sound terrible in one situation can be another person/system’s dream amplifier... usually because of problems in speaker/preamp matching.