Kalium,
Great machine? Depends how you define 'great. It's a shame we couldn't put all that technical skill into an aircraft that had a future.
Great because it could do things that no other airliner can to this day.
Simple as that.
I think in the 70s it was state of the art and definitely had a future. However IMHO there were decades of complete lack of continued investment in developing this aircraft - as far as I can see the only "glass" on the concord cockpit was in the windscreen - I was always amazed by the mass of analogue avionics filling up that tiny space.
The costly upgrade that BA put down as the main reason for dropping concord was evidently well overdue.
In practical terms though and putting romanticism aside I completely agree, carrying on with concord was rather like having a WAG type wife - good for the image but poor for the bank balance.
SB