As a comparison point my Dartzeel NHB 108 [Weiliang /Breeze audio copy] is clearly a class above some very decent amps I have owned .Those amps include Musical Fidelity A5,Rotel Michi, Usher R1.5, First Watt F5,Almaro 318B and Cayin A88T.
I guess some people might want more sonic fireworks and something more load tolerant but if you value finesse ,transparency,subtle high resolution purity, a big 3D soundstage and harmonics /beautiful tone then these amps fit the bill.
Maybe not as good as the better $30,000 -$60,000 amps but probably better than most $15000 ones.