I first bought the Hifiman Edition XS and I was not completely satisfied. I decided to compared them to the HD 490 Pro and after back-to-back testing, I chose the HD 490 Pro by a clear margin.
These headphones have everything I was looking forward in a producer/mixing headphone. They sound warm but clear and detailed. They have amazing bass extension and clarity in the low frequencies. They are the most comfortable headphone I have never tried, surpassing by far the Edition XS. They sound good with no amp but they can sound even better with amp. They have solid separation. They have two different earcups depending on your needs. They are incredibly reliable: they sound good on orchestral music, 60s jazz, EDM, underground hip hop, soundtracks, etc.
I´d say for mid-range headphones, and if you are into production, mixing, or perhaps even a hi-fi man consumer interested in a versatile and comfortable product, these are probably on the top of the list.
I am trying to find a handicap with them but its difficult. The Edition XS sounded a bit wider in soundstage in orchestral music, but the HD 490 felt more intimate and closer while still sounding big, so it´s not even a handicap, just a side note.
The clear thing is that is difficult to go wrong with these. They are incredibly well balanced all across their features.