English Help!!!

First of all, "is more value" is wrong in grammar. It's either "is more valuable" or "has more value".

Secondly, it's either "to Managers" or "to the Manager".

Try this:

Theory A & B are both important but their values to the Manager may vary according to different situations.

OR

Depending on the application to different situations, Theory A & B share the same value to the Manager.