Actually...you don't know if did any good or not during the flowering stage. Only way you could tell is if you had grown another one right beside it exactly as you did this one and not use Superthrive. And even then it'd be hard to know because of the individuality and idiosyncrasies of each plant.

I'd keep using it though if I were you HD as it turned out to be a pretty good second grow for you. Why change.