But my experience wasn't great out of the box.
As soon as I took them out and plugged in the shorter cable (I was going to use it as my daily driver) I noticed it loses contact at certain angles, which makes desktop use very bothersome and unreliable.
The second longer cable seems to work just fine, but to be honest I'm a little disappointed in Beyerdynamic's quality control, hence the 4 stars in quality.
BUILD/COMFORT
Compared to the previous models these definitely have better materials and design but also a stronger clamping force and a bit stiffer earpads, overall they're still a 5/5 to me when it comes to comfort.
Plus they made the earpads and the headband extremely easy to remove and put back in place, which is another big thumbs up.
SOUND
As far as sound goes they definitely have better bass and some more natural, flatter mids than the previous generation, but I had to EQ them in the higher frequencies because they sound a bit dull especially in the 8k region (ironic, given the fact the d990s had a bad rep for having too much of that) and after the 10k peak, where they have a pretty big scoop, this is particularly noticeable in music with lots of cymbals or distortion.
The soundstage is a bit narrower than the dt990s but I believe they have an edge in imaging.
CONCLUSION
Aside from my bad cable, like I said in the title these are good headphones you can use at their best anywhere, and I cannot say that about many other professional studio headphones at all. They have a good sound signature for casual listening, but I think I'd use said EQ if I were to work with sound.
Overall I think they're worth the price and seem likely to stand the test of time.