Exceptional quality, even the slightest detail can be heard. I've send mine to Sonarworks for individual calibration and after that they added a profile for everybody, so enjoy yours with proper calibration! I use them for mixing, mastering, lots of production and recording vocal ideas with them. Every single movement of the DAW parameters is heard and distinguished. You can make such fine decisions and deliver your best work yet.
Without calibration they are closer to how a great pair of monitors sound in a studio room (in my opinion).
For main monitors I use Adam T8V but I mix and master more with the headphones, because it's easier and faster. Translation is perfect every single time. This is a great product overall, I have had them for a long while now and the investment is really worth it.