I am currently listening to that combination. My favored FLC8S filter trio is black/red/gunmetal. I had to tone down the treble from the gold filter, and like the bass. The M1s drives the FLC's quite well, no problem in volume. And even though the Aune has a more neutral sound (to me), the FLC warms the sound up quite nicely. Good solid bass reach, mids are present, but more laid back than other IEM/headphones I own (which is odd, because typically the FLC is quite forward in their mids, to me). Not bad mind you, just different. Bono's vocals on Peace On Earth are very intimate and inviting. This is a good sound.
Coming from my Grado's though, the sound stage is smaller. Playing twenty one pilots Not Today the sound opens up a bit. Still intimate, but not as much as the U2 song. This is a set up I could use for mowing, workouts, walking, cleaning the house, etc...I would call this a solid rich, full sound with slightly less detail than other set ups. It is a good combination, which I could happily get used to hearing. Dave Holland's Hands song reaffirms this nicely as does Car Radio by TWP.
Hope this helps.