User blog comment:SethHeartphilia/Whos stronger Erza or Mirajane/@comment-99.150.248.198-20140424050552

I'd say they are pretty equal. Only that Erza has a slight advantage due to the "break" Mirajane took when Lisanna "died". They are both wonderful mages with extraordinary abilities. Plus in the GMG polls, they basically scored the same in each category.