I actually went through something similar to you, although in a different step. Like class A, A/B or tube not all are created equal. I think once you get to top quality gear it comes down to a matter of preference.
I was bryston fan for years and was interested in tubes but didn't like the lack of power. I started auditioning different class D amps and liked the bel canto's a lot , I thought the nuforce's were decent and the Rowlands were nice but not a huge difference from the brystons. I came across spectron (musician ii) and it was a relevation. I then added another to run mono and had them both upgraded to hybrid plus status. I think spectron does class D correctly and enjoyed them for years. IMO they have the muscle of the brystons and the smoothness and detail of tubes (more of a KT120, not warm like KT88).
I enjoyed them for years but something was always missing for me , and after a while I realized it was the midrange. I could listen to Floyd all day and be mesmerized but it never got Lou reed right to me.
I actually was audioning BAT because I wanted something warmer but I changed my speakers shortly after and heard some of the belles stuff and never looked back. You always gain/lose something when changing equipment for the most part but that Belles SA-100 just didn't everything right for me, I since upgraded my tube pre to a belles LA-01 and the combo with my Vandersteens is breath taking.
You can not tell my set up is all solid state, it has power and smoothness like I've never had in my set up. I did lose some low end but what I gained everywhere else is amazing.
It all comes down to system symmetry but I can tell you for class D the Spectrons are something special.
