Hi,
First, I think the MC Reward is for eastbound on the BA Concorde, return to any BA US gateway in economy.
I used this reward in 1996 for my Concorde flight, I think that anyone who has the chance to do it should, exactly for the experience (and it is neither perfection nor life-changing). What it IS, however, in this ever-homogonized world, is that it is a truly UNIQUE experience, one that few of your contemporaries are likely to share.
With each passing day we get closer to the retirement of these majestic aircraft. Who can tell when the the next generation of supersonic commercial airplanes will become a reality? I say 'go for it' while you have a chance!
(And as a conversation starter, the certificate of flight that I have hanging on my office wall gets LOTS of comments)!
You may also want to use the 'search' function, as I'm sure your question has been broached before.
Good luck.