After several months with these... I think these are my favorites IEMs competing against my FH5 and DM6; hell, I would say I prefer them over my HD600 headphones ( I think FA1 gives me almost the same quality but including this warmer sound that gives the musicality that the HD 600 for me lacks, except for the less refined treble extension cause HD 600 treble is unbeatable)
When I compare them against FH5, you can clearly pick up that the FH5 sound is more technical and resolving, but happens that the tuning of the FA1 is more pleasant to listen to, FA1 has a excellent tunning.
For the price, the build quality, the fit {feels like custom IEMS}, the looks, the isolation, the vocals, mids, the clarity, decent soundstage and separation; it is a no brainier.
About the bass, I feel they sound more pronounced compared to when I first tried them, I do not know if it is burn in or brain burn; what I know is that the bass quality and quantity scale with the source; the bass sound pretty decent out of my OPPO HA2SE. Bass is fast and it has great attack, excellent for rock and metal music as well ad many other genres like Jazz, Blues etc; separation, soundstage, clarity also improves driven by my OPPO HA2SE.
Right now, I'm deciding between FH7 and Fearless S8 freedom, perhaps even the Audiosense T800. I really want something like the FA! but way more technical and and even more details retrieval.