in the early 80's BA had a special to upgrade from first class to Concorde for a nominal fee outbound from IAD to LHR. I took it and it was a great flight, with amazing service. Flight was so quick that there wasn't time for a movie between the lobster.
But, I can see why they finally gave up. Few countries would allow them to fly supersonic (they even had to fly subsonic over the Arabian desert). And, as conventional first class improved with suites and overnight flights, the spartan seats, low ceiling and high price of the Concorde didn't seem worth it.