Just got mine in and so far, these are pretty decent. I can't help but keep comparing them to the Atlas since they are my fave DD IEM.
Wish the JVC had a bit more oomph in the low end, and don't really love that extra energy around 2-4k hz. Coming off the Atlas, the JVC sound pretty forward and small. Very much in your face and little presence of anything around you or individual instruments. I get a strong feeling of someone singing directly into the mic. But, I guess depending on what you listen to, you may enjoy this. For dense tracks, this becomes more obvious and almost sounds like you're listening in a tunnel as everything is just focused right between your eyes.
Ergonomics are a bit weird. They want to keep trying to worm their way out of my ears. I also think they're heavier than the Atlas. While I don't enjoy wearing them down as much, they wear over the ear better than the Atlas does. The JVC reminds me of the Pinnacle P1/PX in this regard.
Also, not loving the stock tips and no foamies were provided. The stock carrying case is also quite small and you can't fit all your accessories and the IEM due to the card the accessories live on.
My nozzles for green and blue were also switched but you can easily see which has more material so not a biggie.
Overall, I do like these. I'd probably like them more if I didn't have the Atlas. But, the more I listen to the JVC the more I keep thinking that is rather be listening to the Atlas.
Just my . 02 cents and initial impressions.