The cable broke within a month without much use and the higher quality replacement costs as much as the in-ears themselves. Nevertheless, as earphones they have much better sound than both the Audiotechnica M40x headphones and the equivalent Shure SE215, which are terrible.

So: Use in two fields; both for listening to music on the phone, and (mainly) for monitoring during live music performances.
I characterize it as an absolute tool, and I will explain the reasons.
The correct requirement for in-ear monitors should be sufficient listening at mild volumes; this is achieved thanks to the very satisfactory isolation it offers, and indeed with good to excellent detail. You can get absolutely decent sound at lower volumes, thus protecting the eardrum from strain. If you are a singer, because your voice will sound to you internally as well due to the speaker and skull vibrations, it needs to be boosted to balance out.
It gives a warm sound, if adjusted with a bit of care, you feel like you are singing in a stadium. VERY SMOOTH headphones....
Very important note: the silicone tips must be the size that "seals" the ear canal, to achieve isolation from external sounds. If they are not "tight", not all the hertz are delivered, you lose bass.
I hope I helped....

vfm for professional headphones! Of course, their use is for demanding gaming that lasts up to 6 hours. In the first few days, my ears needed to get used to them, but now after 3 weeks of use, I don't even notice that I'm wearing them. Amazing isolation from external sounds, as for their quality, everything indicates that they will last a very long time. 10 out of 10 from me!

I have used many headphones for professional use on stage. They have by far the best sound of all! I am absolutely satisfied

Well, these headphones have amazing sound compared to other much more expensive ones. Nice clean and fast bass, and warm highs. You can't call them flat, I would say they sound more like a V shape. The sound stage is not crazy, but it's there, at least in my opinion. (tested on a mixer and mobile)
*You have to wear them correctly and with the appropriate ear tips for your ears, otherwise you won't get what they offer!

What you pay is what you get, and let's not forget that SOUND is a subjective matter, so it would be good to try them out if you have the opportunity before making a purchase. For me... Pure disappointment... They lack bass! We fell for the BRAND NAME and even more so for the fact that they claim the product belongs to the PRO series. Unfortunately, I was taken in by various reviews and simply... WASTED MY MONEY!

I can't imagine better at this price. I prefer them over the other headphones on my ear. I would recommend them without hesitation.