I am not fully "tubed" yet, but am leaning in that general direction.
For my desktop system (computer), I am using one of those little Chi-fi amps, a TubeCube | 7 (same as the APPJ) that uses a pair of EL84s and a 12AX7. I recently rolled in new-issue Mullards to replace the stock tubes, and it sounds quite good. It is the best I've ever heard on my desktop, even if the amp isn't all that good.
My main rig only has a tube preamp, a C-J with a single gain stage powered by Mullard M8080/CV4058 tubes. Very nice, and is surpasses the Halfer it replaced, as you'd expect. I currently use the Nelson Pass-designed Stasis power amp (Nak PA-7). Pass is known to make solid state amps that sound very tube-like. Some of his designs, like the Aleph series, were based on Class A and generate all sorts of heat and use a lot of power (as in, 2x to 3x as much as the amp's power output rating). You'll be best friends with a large electric bill.
The Pass Labs amps of today are very expensive; there are actually higher-end tube amps which are less expensive than some of the Pass monoblocks! If my amp is already quite good, how would a tube amp change that? I'm not into making expensive sideways moves, nor do I want to own an amp as a status symbol.
But that brings up a point. Some modern tube amps are known to have none of that familiar "tubey" sound, and nearly come closer to resembling solid state power amps. I have heard some of them at AXPONA and have no real opinion on them, due to unfamiliar speakers, the music, the room, etc. (Don't get me wrong--they all sounded fantastic, but I could only compare two amps in my own system to make a decision.) Point here is that the best solid state and tube amps do not have that much differential between them, as they did in the past. I think it is more about deciding what sounds best to us in our own systems, vs. worrying whether it is tubed or SS. As for vintage and near-vintage (maybe a dozen to 25 years old), those designs may be more of what we are after when we think of tubes.