@HiFiRobot, do you primarily use Spotify? I ask only because of your signature. I just signed up for the premium subscription service to a/b test it with my Google Music All Access subscription for audio quality, specifically for these UM Pro 30s. You have a preference strictly from an audio quality perspective? I also realize this topic has likely been discussed a million times over, but maybe not with regards to these IEMs.
I primarily use J River with WASAPI playback. But Spotify more and more but mostly when on the go. Just hoping for Spotify to catch up with WASAPI support. I haven't tried the Google Music streaming service. But I think What Hi-Fi has compared the SQ of different streaming services.