This might not be in a class with some of this other gear, but it's a small form-factor amp that I own, is pretty versatile, and sounds at least decent to my ears...my Sherbourn PA 2-50. Perhaps the best thing about it is its versatility...2 RCA inputs, 2 PAIRS of speaker outputs, remote control, automatic switching on. I've got it in my office system, powering Kef 103.2's stacked on Bozak 305's and it sounds pretty damn good. In the past I've used it to power big Magnepans, Kef LS50's, and Kef 107's...it handles them all (not saying performance will be optimal with only 50 WPC, but it drove them all fine).
I'm about to build one of the small, cheap DIY tube pre-amps for some tube flavor, to see whether I like it or not in this system. The Sherbourn sounds fairly accurate, if not a bit sterile, so maybe some tube coloration will make the system a little more "fun."
Either way, I bought this unit NEW for only $169 on closeout, with a 10 year warranty. Happy with it so far, over the last 3 years or so.
Edit - added under the hood pic