I've now spent a few days using the Antipodes K50 with the Premier DAC. Before getting it I was slightly worried that with MSB doing their best to isolate the DAc from upstream source variations the addition of a streamer/server would not yield any tangible benefits to the sound of the DAC. That is definitely not the case! Even though the MSB sounded great fed directly from my PC (especially with their optically isolated Pro USB input), the Antipodes takes the sound to another level. Increases in cohesion, flow and tonality are immediately apparent, and everything just 'gels' more, especially vocals.
I'm still experimenting with which output is the best, as they all sound good but slightly different. The new USB output that was implemented with their latest (G4) upgrade sounds excellent, and pairs really well with the Pro USB of the MSB using a FTA Sinope Cable. But AES (Jorma cable) also has its charm, maybe a tad less clean than USB but also a little more musical. Even Ethernet out is surprisingly good, maybe a happy medium between the two.
Other benefits include: not having to keep my PC on all the time anymore, a superb build quality for the case of the K50, and a super responsive and helpful after sales service from Antipodes.
So in case you couldn't tell, I highly recommend the addition of a streamer/server to MSB DACs. Even if one doesn't want to spend big bucks on the K50, a K30 or K22 or even one of their older units would still bring sonic benefits to the DAC.