When someone says they are upgrading a product it usually means getting a more expensive one. Although in my audio journey I’ve found this to be true of cartridges, with each more expensive upgrade bringing a greater performance. However last spring I decided to upgrade my handmade British solid state integrated amp with the latest greatest model. I got in before the tariffs at 6.4k and after 6 months the amp jumped to 9.3 k. Then the old guitar player in me wanted to try a tube amp. Ended up with the UFO2.1 and after comparing the two amps I boxed up the solid state and listed it on AudioMart. I couldn’t listen to it after the Decware. I took a chance sight unseen and even with my TAD speakers with an efficiency of 85 I never run the volume past 1 o’clock. I was then intrigued by the open baffle speakers so I purchased the pair advertised here that were from the Weiss estate. They too are fantastic and give a different sound signature than the TADs. But considering the open baffles were $700 vs 18k for the TADs it is a better value. Lesson learned you don’t need to spend more to get better.

My mind tells me that my 2017 built basic zenufo was my best ( or favorite) sounding amp I had even out of a small fleet of other Decware amps including Rachael / Torii Jr v2 / 2.1's . Since sold the only way I'd be able to confirm if I got it back. I replaced it but my first still calls to me.
Up grading can get expensive and not always an improvement. Now if one could purchase synergy itself ?