The main advantage is that it was very fast. However, the disadvantages were that it was very expensive and not very efficient in terms of fuel (which is why it was expensive). Not very many passengers could fit in the plane and it used more fuel per passenger than a subsonic flight would.
The advantages were handling , safety and supersonic speed . Disadvantages were the noise , pollution and the fuel consumption.The main benefit of the Concorde program was the design and manufacturing experience.