Omg. Same old story “a huge upgrade”, “punches way above its weight”, “in a league of its own” etc etc. a new option in the 600 series. Yes, it costs a little more as Sennheiser is a business after all. Give it some time and the price will either settle down or the sales will become more frequent. The sound better be different than others in the 600 series and even the 660S or why would you be buying these. Just grab some of the music you like and audition these, and if you like them - pull the trigger, if not - there’s plenty of fish in the sea. There’s no end game single set of cans and there’s no single set that does it all. Enjoy the music and happy listening.

PS: and please try to explain the sound with music examples and how it sounds to you. How instruments and sounds are pictured in your mind. Stop using “mids” “highs” and “lows”….