I have not heard every $500 modern nor vintage integrated, but I don't think that the claims that vintage integrateds can be excellent value are exagerated. Here's my experience:
I own three integrateds for secondary sound systems, a Musical Fidelity A3 (paid $650 used), a Scott 222C ($250), and a Scott 299 ($300); I have also borrowed and listened to, a Creek A50 ($500 used). The two Scotts are similar enough that I will refer to them as one. It is true that the two modern amps (MF, Creek) are "cleaner" sounding than the Scotts, but in a HI-FI way. Are they "faster"? Not according to my definition of speed. The Scott's have the tube magic and musicality. They let subtle musical phrasing details come through that the two modern ss amps do not. They simply sound more alive, the sound is more active. By comparison, the two modern amps, particularly the MF, can sound dynamically dead: A dead corpse in a new, shiny, well pressed suit. Images have body and density with the Scotts, the two ss amps portray outlines of the images very well. The Scotts give you three dimensional images drawn with soft-brushed strokes, instead of flat images drawn with a sharp pencil, as with the modern amps. The Scotts, for some reason, let me enjoy the music, instead of always reminding me of how much better my main rig sounds.
The key here is, I think, price point. There is Jolida, and I'm not up on what used Jolidas go for. Also, I am pretty sure that something like a used older Audible Illusions (tubes) preamp mated to something like a used small Adcom (535?) for around $500, would beat a used Scott; maybe.
Good luck, I highly recommend the vintage route; at that price point.
