>>106583962
Because it's decently comfortable and has low distortion. Frequency response is not terrible either. If it doesn't sound good enough for you just EQ, it's literally free improvement.
>>106583997
Corsair Virtuoso Wireless or HyperX Cloud Alpha wireless. Though a used Maxwell would still probably be miles better than those.
>>106584012
Better build quality, lower distortion, better tuning etc. HD620s is limited by bass distortion like most DD headphones.