Why Saitama is so Awesome?

There are alot of reasons Why Saitama is so awesome?
Qualities of Saitama:
He is so calm even in the battle between the Strongest Enemy of the whole series. He act like nothing happened. He love Shopping. He got a great body and he can run with the speed of light. His Punches Plays an important role in Entire Series. He can finish any enemy with his ONE Punch and that's why The Series Known as One Punch-Man.
The most important Part is " He can go to the moon and come back for FREE.