M0 is much lighter and cheaper and uses USB-C instead of a proprietary cable. The feature set is roughly similar (audio formats, USB audio, BT source/sink, etc.). It doesn't offer any media sync software, though. DAC should be good ("ESS Sabre ES9218P") but honestly I can't tell the difference between Apple's own 3.5mm-Lightning dongles and fancy audio equipment. At least it's not obviously noisy.