Filing a writ or a suit- which one is better?

Hi, 

A act of wrong restructuring & subsequent npa declaration by bank is to be challenged before the court of law. Till now sarfaesi has not been invoked by bank. I see two ways to challenge the bank actions, through a writ or a suit.

Which one, writ or suit, is better equipped & applicable to address the same keeping in mind the wrong restructuring & debt recovery matters?

Thanks.