Pro Equipment

This is one of the best headphones I ever heard. I heard it carefully and compared with other 10 pro tops. The environment was very simple, it was plugged in a portable CD with no reinforcement features, playing a Spyro Gyra tune. It sounds like a monitoring system with flat response, what makes it a reference equipment.
Despite the well known advice not to master and mix tracks with headphones, some works I did with this equipment (only) sounded awesome when submitted to the studio monitors.
Since this kind of equipment is not intended to use outside a studio, portability doesn't matter.