Vacuum tube designers learned early on to minimize tube count. I imagine it got to be reflex.
Right. Or they took a look at the hundreds of designs out there already and selected for cost, sonic quality, and tube availability.. and maybe gave it a couple little tweaks. Don't think they came up with a unique design or it'd be labeled patent pending?
Make it work properly?
I'm sure there are "closer to reference" amps out there, in fact, I know that my hafler MOSFET amps would 'measure better' in every way on a lab bench...
But I don't know anyone who has lab grade unbiased ears... 'sounds better' is subjective, yes you can build an amp for the same price. I'm saying this amp has a wonderful and deep soundstage, it has a warm clean sound, it looks decent, it's got a phono stage, and the Bluetooth supports aptx hd which has a higher bit rate than a wired RCA connection.
This amp works miracles to hide compression and bring crisp warmth and depth from streaming music.
This amp sounds great with great speakers but it also will seriously impress any audio snob just connected to moukey m20-1 and a Polk psw10.
Tldr: The price performance is unrivaled in the space. Benefits greatly from replacing the Chinese tubes. Monoprice will send you a new one if you accidentally break it. And you have 30 days to return it.