I have both Beyerdynamic DT 1990 Pro MK II and the DT 1770 Pro MK II, and I have to say, I prefer the open-back 1990's wider soundstage. Because of that, they're more balanced than the closed-back 1770's. However, both have phenomenal fidelity, especially when paired with a good headphone amp (even though one isn't required).
Not to mention, they're suuuuuuper comfy, and are built extremely well, and a re largely user-serviceable so you can't go wrong.