Testing these now from an ibasso D7 - really nice lush/solid sound, a little amplification really helps them out.
The Atrio M5 has tighter, punchier bass whereas the ASG-1 bass is a little more prominent. Midrange on the M5 is a little less forward and the treble is a little more sparkly.
Essentially the ASG-1 has a warmer, heavier sound to them - it makes them a great match for rap/hiphop/dance/trance/electronica.
Special mention goes again to the quality of the ASG-1, it's good to see manufacturers putting a bit of extra effort in to make their canals last longer