Saitama and Mob other than being very very powerful share very little in common.
Saitama wants to be a hero, Mob wants to be popular.
Saitama wants a challenge, Mob wants friends.
Saitama will most likely go on to not be challenged ever, Mob has been challenged by external factors a lot, while his true limitations are internal.
Saitama is issolated and his relationships were born out of extreme circumnstances and could do without them, Mob has worked hard to make friends and understand his rivals and his brother.
The stories share some elements, but they are very different in what they want to accomplish.