For a 3-way at this price point it works good....There is a but...
This is a monitor and will sound very flat, cause it's not at flavored In ear "speaker" it's a monitor that's made for you to find over boosted highs and mids, it's not a low end power house, but it's good for hearing the low-end and if you are clipping.
But do not adjust the eq for low-end with this in IEM it will sound absolutely horrible. when it hits a "normal" speaker.
These will be good for any instrument monitoring, if you are not on drums, or base.
My personal use is for listening to speech, and music and video sound mix, and it does it great, with the right amount of EQ it can be a okay listening experience, stereo picture is very good, again it's a monitor it is supposed to be good.
I use primarily the Silicone ear tips, not the foam, cause I want to be able to hear what going on around me, the foam tips isolate more, but still not completely, my rating is compared to a closed back headphone.
There are better alternatives out there. but they are often double the price.
The IEM it self is not like a custom made product, and I get that, and for the price it's comfortable, but there are some "sharp" edges, that would have been better it they had a more organic form, depending on your ear it might not be the greatest thing, the wire should have come with an angel connection from the monitor it self, the monitor quality is great for the price and after using this for quite a while and seeing up to approx 9-12 hours of use a day , without discomfort.