Weighted GLM functional connectivity or gPPI

Greetings, 

I am currently assessing whether a cue reactivity task modulates functional connectivity. I ran weighted GLM functional connectivity analyses at the first-level, and at the second-level, I fail to see any differences between my two task conditions (from two different sessions). Each task condition is associated with functional connectivity maps that overlap. Would it have been more beneficial to run a gPPI analysis to assess differences between conditions, or would it yield similar results? 

Thank you for your assistance, 

William Denomme