To partially answer both Nrchy's and Onhwy61's questions (How long has your system been the same? What valid conclusions can we draw from the observations of others?) as they regard myself, here's some news FWIW:
Yesterday I bought an amplifier from a local Agonner, paid cash and picked it up. I did this not because I necessarily wanted a new amplifier, but because I've been planning on doing some modifications to my current amps (capacitor upgrade) and wanted a spare. However, I do confess to having another, additional motivation. My regular amps are VTL MB-185 tubed monoblocks, but for a while I have been somewhat curious to see how I would react to a modestly-priced solid-state stereo amp - like the ones I used have a few years back before I got my previous C-J tubed stereo amp, only more up-to-date. Call it a reality-check.
The amp I got is a McCormack DNA-125. My reference amps cost about $5K new, the DNA-125 about $1.7K new. Truthfully, I am still only warming this thing up, as I literally inserted it into the system less than 12 hours ago. But already I can tell there are some things it does at least as well, if not better (or merely as well but differently) as my reference. Based on my past experiences, I was in no way expecting to be seriously tempted by this amp, and probably planned to sell it once my mods were done. However, I admit that part of the reason I'm auditioning something else now, before I do the mods to the VTL's, is to confirm in my own mind whether my reference should be a 'keeper' that I sink more money into, and also to double-check my overall commitment to tubed power by bringing in something solid-state. That the comparison could be called 'unfair' from a price standpoint (the output power isn't very different between the two into 4 ohms) I'll just have to let slide, since I wasn't going to drop much more than I did for a presumed temporary experiment.
But this little McCormack is obviously a very fine performer, maybe even 'good enough' - if we can ever admit to such a thing in this hobby - and I am going to enjoy listening to it for a while. Anyway, to get to the question touched upon by this thread, I just returned from rereading Jim Merod's review of this amp, and then going to audioreview.com, where there are 35 user reviews, who gave it an average of a perfect 5 out of 5 rating. And let me tell you, both Merod's piece and almost all of the user reviews are, I think at this early stage, dead-on acccurate in their assessment of this amp.
Now, this may not mean much in isolation, especially since it kind of surprises me, as I routinely find myself disagreeing with reviews both professional and amatuer. And, of course, I have a ways to go with this amp before coming to any final conclusions - there are still things I suspect my reference does better, although in terms of value for the money I likely have some thinking to do. But clearly, this McCormack is doing many things seemingly 'right', and everyone I've read about it so far thinks so too (next stop, Agon archives). That's got to mean something I believe ; that kind of consensus, jibing as it does with my own tentative experience, cannot be easily dissmissed as devoid of significance, at least not by me...