Their sound is impressive. Very clear across all frequencies. And powerful, which is not obvious (e.g. I had bought the 1More Triple Driver but they didn't have a strong enough performance). It transforms songs compared to cheaper headphones. Very high-quality construction.

Generally, I am not one of those people who easily fall victim to hype, so my review is quite objective. After weeks of searching for headphones, I realized that over the ear ones are not for me, as they gave me the feeling of having two small speakers very close to my ears. So I ended up with in-ear monitors. The FH3 had very good reviews everywhere (although the same was true for the Beyerdynamic 770 pro, which I thought were terrible). Since we don't have many options for IEMs in Greece, I ended up ordering these.

Their construction seems to be very durable, and indeed, when you hold them in your hands, you understand that you are holding something expensive (by Greek standards). Their sound is as described by most of the reviews, with a strong sub-bass that is crystal clear and does not degrade the other frequencies. Their mid-bass is not as strong and pronounced as I was used to from my previous headphones, but with such a clean and full sound, I can't say that I miss it much. I think if you are coming from cheaper headphones and looking for an upgrade to in-ear monitors, you can't go wrong with these (unless you don't like sub-bass and are looking for flatter headphones). They are headphones that can perform well with almost all genres of music, although their forte is definitely EDM tracks. Finally, I can't say that their soundstage is ideal, but for IEMs, this is expected.

I hope I helped the undecided ones a little (since I am one of them), just make sure that their sound signature is what you are looking for before making the purchase.

EDIT: After 8 months of use, I have to say that this is the best purchase I have made in my life in general, not just in audio products. Every day I listen to songs that I had heard in the past, and they sound completely different. Just know that now there is no chance of me listening to songs from YouTube or mp3, only Spotify premium, as the difference is huge. Also, in general, you won't be able to listen to music with other headphones again, at least I can't tolerate any other wireless headphones even during my workout.

TERRIFIC headphones BUT:
1) In order to fully enjoy their true sound, at least on a PC, you need a headphone amplifier (I got the M-Audio Bass Traveller and the difference is night and day) and
2) You can hear their true sound after about 200 hours of headphone usage, so be patient.
Also, make sure to use the right tips that fit well in your ears because otherwise you might feel like you don't have any bass, and it will be due to the fit and not the headphones, which actually have incredible bass.

Very good, they emphasize bass and mids and not so much on the highs (not that it's bad, just not "sparkly") and they provide a very nice "warm" sound. If you're looking for something quality with great imaging for the money and don't want a flat sound, I recommend them without hesitation.

If you're looking for something in this price range and haven't decided, I would suggest these, the Mackie mp240, the Moondrop Starfield (although I don't know if you can find them in Greece) or the Meze Audio Rai (for a little higher price)