Has anyone made the jump to $uper High end and were disappointed?

"Room, electricity and isolation devices". Fully agree. I would say electricity first, isolation second except for turntable, maybe.
I would also add to that cables and power cords. Many seemingly have no idea how good their active components are because they are connected with mid-level cables. Real high performance usually starts at over $1k a piece or for a pair. Ultimate performance is much more. Personally, I like to have cables at least one step above active components.

inna: my experience is that the electricity can be good, but if your components are vibrating, you will lose the musical lines in a symphony or anything else. I have tried nearly everyone’s isolation feet: Up until a few months ago, I used Nordost and Stillpoints footers (more the Stillpoints than the Nordost. Much more.) But one day, 3 or 4 months ago, I came across a thread asking about the latest generation of the Townshend Seismic devices. (I have a Seismic Sink, which I’ve had since 1994, which I can’t use because I don’t have the pump for it.) I hadn’t really thought of them, although I had Townshends ribbon tweeters 3 years ago. After reading the thread and then the review on Positive Feedback, I thought, hmmm... why not try out their current isolation feet? (I could always return them if they didn’t work great.)

WHOA! New ballgame. Neither the Nordost nor the Stillpoints did what the Townshends do, which seems to be, to remove ALL vibration (but again, the footers must be placed EXACTLY). Not being a technical anything (!), I can’t speak to the technology, only the results. The sound field is much larger, as though I moved from row 15 to row 8 in Carnegie Hall. The musical lines hold together fairly well (that’s the speakers’ limits) even during an fortissimo. A tuba actually "breathes" and you can hear the "blattiness" that makes it so distinctive. In fact, the whole bass range is extremely "present." Now, my electricity has always pretty good. And I’ve had Audience Adept, PS Audio, Bybee, and Shunyata AND Nordost power conditioners. All very good. Sound was great. But when I put in the Seismic Platform (under my turntable), that was the moment I realized that vibration was a major player, too. And, even with the platform, it took me at least 2 months before I realized that the feet needed to be optimally placed under the component and rotated (they’re on a bolt, and can be moved upward and downward). I put it in 3 other systems I set up for friends and had to adjust them each time (just the height of the pods themselves mainly, but as I moved them underneath the equipment front to back and side to side ( I had, by that time, also gotten a set of just the pods with no platform on top of them, because I knew I'd have to insulate the preamp as well as the turntable), I could hear the difference between "great" and "exceptional." And so could my one friend, who goes to the symphony every two weeks and listens to music (on his stereo) without speaking until the song is over. We played "I Am A Rock" (Simon and Garfunkel) and the second time we played it, I had rotated the isolation pod a minuscule amount. And I DO mean MINISCULE. Nonetheless, suddenly - as he put it - "I can hear AIR around Simon’s voice." And he was right: I heard it as well. (You could also hear how nasal Simon's voice was: it was like hearing INSIDE his head, it was SO evident). I wrote the importer, Dan Meinwald, and told him what I’d observed about the placement, the rotation, everything. And he agreed. Not only that, but the springs on the damn thing must be COMPLETELY VERTICAL. It’s possible to have the bottom part of the spring slighted angular from top to bottom. Imagine a clock and the springs angled at a 1 o’clock - 7 o’clock positioning. Nuh uh. It HAS to be VERTICAL: NOON TO 6 o’clock ONLY. Don’t know why that's so. Just know that it is. I subsequently learned they must be - one at a time - raised and lowered for the very best results so that, if I’m playing, say,  Abbey Road by the Beatles, I can hear Paul and John’s voices separated in space and in harmony and can follow each one individually.  Otherwise, without that exactitude, that last piece of "magic" is just not there.

So, I put complete isolation right up there with electricity. And now I know why people have gone thru such lengths as putting the equipment in an adjoining room, but how many of us can do that???  And, of course, the room itself, which, without "fixing" it as much as possible (I have 30-40 tube traps), will still leave you in the dark about how good your system actually sounds. I would tie all 3 together in first place. Any one of them out of whack, and the proverbial cake will fall flat. It’s no surprise to me that people argue (and not very nicely these days) about whether any given device is as good as others say.

gbmcleod, you must have a very sensitive system. I didn't really experiment much with isolation devices. The biggest difference for the better I heard was when I put Boston Audio graphite tuning blocks for speakers under speaker spikes, I use Polycrystal not steel spikes. Big improvement in everything. Howerver, I have free resonance speakers that do have excessive resonant energy. Another example, much smaller but still significant, is that I put one 1/2" Walker resonance control disc near turntable motor on the maple block the table sits on. The maple 3" block is in turn sits on three big Boston Audio tuneblocks. And all this construct is on a wooden floor, no rack. I tried to put the second Walker disc near tonearm on the maple block and it got a little worse. And just one disc near tonearm made no audible difference. I also put one Walker disc on top of my Nakamichi cassette player - same improvent as with the table. And my integrated solid state amp definitely sounds a little better when sitting on brass Audiopoints than on Boston Audio tuneblocks. So yes, isolation is very important, though I call it tuning. But I don't think my sysytem is as sensitive as yours.
Electricity here is terrible, just terrible. Very dirty and voltage fluctuates almost constantly. Without my PS Audio Premier regenerator the sound is unacceptable most of the time. And I mentioned power cords, older Purist Audio Dominus did wonders when was put on the integrated.
So, my advice would be to learn how to fully tune your existing good set-up before moving much higher, or it will be a waist of funds and nervewrecking experience.

Is a waist of funds kinda like a money belt?

Of course there is a curve of diminishing returns. With respect to high fidelity, it is asymptotic to the recording being played. I learned a long time ago that, for me, sound quality doesn't get better and better and better, no matter how much money is spent. Not that I would necessarily be disappointed with a much more expensive system. I'd expect a little more air than mine, and more bass definition and extension. I'd also expect it to play a lot louder. But while the ($200K?) system in the Rockport/Boulder room at RMAF 2016 sounded wonderful, it didn't sound any better than mine, to my silver ears at least. YMMV.

Sorry to be so disagreeable but I found out that all this audio stuff is actually NOT (rpt not) asymptotic. There is no glass ceiling. There is no law of diminishing returns. The reason for my statement is that real sound quality SQ, not what you THINK is SQ, is not connected at the hip to system cost. SQ is, however, connected at the hip to how well the person can locate problems that are there in the system but not obvious and fix them. Either with tweaks, aftermarket fuses, isolation, what have you. You cannot expect ANY electronic component to make up for these “hidden problems” no matter how much you spend. That’s why a well thought out inexpensive system can sometimes beat an expensive system that is simply plugged in and played. That is why a lot of folks who have 30 years of experience in this hobby still have mediocre sound. No offense to anyone living or dead. 🧟‍♂️