The suggestion that Simaudio is in trouble is disgraceful and unfounded. Their North collection is flying off the shelves on the back of superb reviews (and listening).
I have not heard the 390 specifically but have done with many other Moon products from the 300 series to the current mix of 600, 700 and 800 components in my system. They are unremittingly neutral with an extremely low noise floor, in other words you get exactly what is on the disc or file.
I find the Android app to be intuitive and it regularly updates seamlessly. One thing to note is that the MiND 2 unit in the 390 is the same as in the MiND 2 box and my own, much more expensive, 780D DAC. With the 390 you are getting the best they do.