These are the best In-Ear headphones I've ever used, and it's not even close.
I spent hours trying to test the limits on them, and they relentlessly smashed their way through everything I threw at them. Rock, Pop, DnB, Hip-Hop, even Classical and Acoustic. Everything sounded fantastic. There are songs I've listened to for years, and with these headphones, I'm hearing parts I never knew existed.
All frequencies are extremely well-represented, and with unbelievable clarity. Even in tracks with intense bass, the highs and mids remain crystal clear.
The headphones themselves are well-built, yet nice and light. Other "premium" in-ear headphones I've used tend to be a bit on the heavy side and fall out during regular use. I've had these for about a month now, and I have yet to have that issue with these. The isolation they provide is great as well. The headphones come with 4 different sizes of tips, and finding the ones that give the best fit (a snug seal) is key.
My only regret is not getting them sooner. They're amazing, and I'd recommend them to anyone and everyone.