I think it costs a bit more than regular first, and a lot more if you want a day return, which isn't realistic on subsonic transport. Its easy to say it skims the high-yield passengers from the subsonic services, but thats based on the assumption that those passengers would choose to fly on other BA services. The speed and the prestige are the attraction of Concorde, once you strip those away the passenger may well find they get better value on another carrier?