Received Moondrop Echo-B a few weeks ago, it's *OK*. The DSP function is very wonky. Changing EQ causes the device to restart, pausing playback and interrupting the connection with the Moondrop app. I sometimes have to re-seat the usb-c connector to make sure the app is actually reading from the currently connected device and not just changing phantom settings like it constantly wants to. Also seems like you have to register a Moondrop account to set custom EQ.
Sound quality is fine and it drives my Harmonicdyne Eris headphones adequately. Build quality is fine, cable is fine. Looks nice.
If you want DSP function, look elsewhere. Though I'm not sure why you'd buy this thing over all the alternatives if not for the DSP function..