@soix: I’ll see if I can find that Soundstage review. On Audiogon, though, other Hegel owners have told me that there’s a big difference between the analog sections of the 390 & the 590, and there’s a big difference between the DACs of the 590 & 600. Opinions diverge a lot about everything else, and I understand that context (as in associated equipment, power, and room) makes a huge difference, but those two comments have been pretty consistent.
And I could be wrong, but I think the first time I compared the 390 & 590, I found that the 390 did not have all the 590's connectivity options. (Surprisingly, the same is true of the H600, which is supposed to be a 590 upgrade!) But I’ll go back & take another look, b/c I'm not sure about that at this point.