I'm not sure I would trust a manufacturer who can't get mV vs. µV straight in their specs.
Also, several hundred µV worth of output noise even in the lowest-impedance setting? That must be very much non-white (e.g. 1/f) and/or measured improperly, otherwise the OP would be running for the hills even with the (measured) 98.4 dB / 1 V AB-1266 and not making any claims concerning blackness, unless he's half-deaf of course.
SNR with given output power and noise specs comes out to 90 dB... which sounds halfway acceptable until you realize that even in the 32 ohm setting maximum output is about 12.6 Vrms... +22 dBV. That means 120 dB SPL (ish) with these cans, and noise at 30 dB SPL (ish).
Oh, on the pictures the cans (47 ohms nominal) look to be plugged into the Hi-Z (300 ohm) output. I can't imagine that's a particularly good idea, output impedance may well be 100-150 ohms like that. I can't help but think of the old saying about a fool and his money.