The HD 620S was their first audiophile headphone and they love it for its comfort, isolation, durability and punchy bass, with natural sound on many genres; it isn't as expansive as the HD 800 S.
“HD620S are comfortable, durable, look nice, punchy bass, and many genres sound relatively natural on them especially after letting your ears get used to them. They were my first audiophile headphone and I will defend them to my grave.”