X-Sabre MQA uses the xmos xu216 chipset for usb, which is the latest and greatest (Native dsd 1024!) and only one other dac is using it. I actually prefer the usb over the Allo Signature transport. Did need a long time to burn in, approx. 400 hours to settle to it's final state. Unlike the R2R dacs, there is no warm-up time for it to sound optimal. IMO the Matrix MQA bests the Benchmark & Mytek Manhattan 2 dacs I've tried. It's a great second dac that compliments the Yggdrasil A2 nicely. Talking with Arthur of Matrix, he did mention that the older Pro version sounded pretty much the same minus the MQA encoding and older u208 xmos. Those have been going for about 1k used.