A couple of points about the amps: 1. Amp differences are measurable. You can find scientific results and graphs in every issue of Stereophile. These tests are repeatable using a variety of test equipment. They meet scientific scrutiny. However, I will grant that it may be difficult to tell amps apart in listening tests. Also worth considering is that the "all amps sound the same" tests intentionally exclude various topologies and/or tubes. My reading of that is that all amps sound the same except for the ones that don't. If you were to stack up solid state against DHT, push-pull, SET, etc., the differences would be both measurable and heard. 2. There are wide differences in amplifier build quality. A lot of the cheap ones are, well, cheap. If you're cool with a third world el discounto power transformer smoking off after a few years (and assuming you have proper insurance coverage and, hopefully, a sprinkler system and fresh batteries in your smoke alarm), then you can save plenty of money. If you want an amp built correctly with reliable parts, you will have to spend some money. Further, the cheap tube amps are on PCBs, which can be difficult or impossible to repair if something goes wrong.