I cannot comment on the 30.8 but the XA25 is a superb amp, utterly transparent, that will drive my Rockport Atria IIs easily. It is revealing of poor recordings however. You hear EVERYTHING that is on the source, a singer's breathing, a a guitarist's fingers on strings and decays that last forever. On a piano you are aware of the shape of each note.
It is rated at 50 watts into 4 ohms at .1% THD, class A.
My setup is Aurender, Esoteric K-01XD, Benchmark LA4, VPI Scoutmaster with Koetsu RSP. Cardas cables.
I flip back and forth between the XA25 and a premium Elekit 8600S and love the sound of both, the revealing, detailed (but still musical) precision of the XA25 and the more organic, concert hall like, presentation of the SET.