I am having a bit of a love in with the AKG K550s at the moment
I got them as a one off as I needed some closed backs. Sold my HiFiMan HE-6 to pay for them, and got a Beresford BM to drive 'em. Mainly using for movies but also stereo music.
All I can say is, I am not missing the orthos nearly as much as I thought I would. Sure, they were better and in a different league. But the £600 change I got back from the switch has kept me in movies and music ever since
For £150, they really deliver. Ded comfortable and very smart looking. Nice deep bass slam (i am sure the BM helps, and Stan tweaked the gain to match the AKGs which is nice), and the fine detail off a bluray movie is stunning, really immersive.
Thoroughly recommended as a closed back option!