Since this seems to be the most popular E3 thread, I will add my comments here instead of creating a new thread:
Got it a few days ago and while the sound is pretty good, it has some annoying quirks:
1. It doesn't play at 44.1/16 sample rate in Windows. Foobar confirms this:
Not sure if I did something wrong when installing the drivers, but I can't get it to show 44.1/16 sample rate in the control panel.
2. It has some small amount of internal memory and
it saves part of its configuration even after disconnected from the PC.
I haven't tested this quirk with every features but with volume I am 100% certain it happens: whatever is the volume you have it when you disconnect from the PC, it will have the same internal volume when you connect it to an android device.
This is kind of annoying because it handles volume slightly differently in each device:
On Windows 10, its volume buttons control the general PC volume when it is being used as the output. In principle it should be feeding the DAC with the full data stream and them regulating the volume solely with the amp, but you can't tell for sure since the volumes are not separate.
On android (6.0 on a Nexus 5) with OTG cable: when you press the volume, it controls the overall system volume, you can even see the standard volume slider that shows up when you press the volume keys. Again, you can't tell if they system is feeding the DAC at full volume or not. The odd behaviour here is this: if you go to the PC and lower the volume and then plug it into the android device, you get an overall low volume. It is as if the internal volume set on the PC is saved as some kind of baseline volume and then it is controlled as fractions of this baseline volume. Weird to say the least, but I tried several times and can confirm it is 100%.
On android (6.0 on a Nexus 5) with bluetooth: this is the only situation that it seems to behave "correctly" as a DAC/AMP: Bluetooth volume in the phone is independent of the volume in the unit itself. Still you can't be sure it is regulating the volume solely with the amp.
3. On all 3 modes it has very annoying problem with system sounds:
On Android, if music is playing, it gives high-pitched noises (annoying and sometimes even painful) whenever a system sound plays. If no music is playing, then it just clicks, but in either case it doesn't play system sounds correctly.
On the PC it also happens though less often and not consistently.
4. Its amp is indeed "too much" for IEMs. It runs at minimum volume with my Sony XBA-A1 and still I can hear sometimes ground noise. With my Fisher Audio 150ohm (can't remember the model name) it runs beautifully, powering it very well.
The issue with 44.1/16 is strange to say the least:
How can they say that it plays at 44.1/16 on mobile devices but it doesn't on PC?
How is it possible that NO SINGLE REVIEWER noticed this?