Here is the thread in these forums for the DT 770: https://forum.hifiguides.com/t/beyerdynamic-dt770/116
Based on my time with them as a user myself, I like them: I use them for their passive isolation when others are around me and they do their job keeping my music to myself quite admirably, and with their durable construction/sturdy feeling is as described I have no issues with the build quality apart from the cable being nondetachable unless you mod it yourself. From the website you linked, there is not really any meaningful details on the sound quality itself, and the discussions on sound quality for the other entries don’t seem all that reputable either. To my ears, they are objectively V-shaped (bass/treble emphasis, bit hollow in the mids/vocal ranges imo) with decent detail, adequate soundstage/width (for a closed back). They are the best closed backs I’ve used for under $200 with a more consumer-oriented sound signature, I prefer them over the M50x with similar sentiments as others have stated above. However, they aren’t my cup of tea for their specific sound characteristics as I usually roll with something more mid-focused like my HD58x. The DT 770 thread I linked also has more discussion on the various iterations of it with different impedance levels.