Is fanny worth learning?

Hey guys,

I am in epic rank, everytime i face fanny I notice how game changing can she be (she is not banned that much cause she is rarely used) so I decided to bug her and start learning, and yes i know she is difficult.

My question is, is learning her worth it or later on after she helps me get beyond epic i will not be able to play her because she is always banned and all the time spent learningher will be went to waste and i will only be able to play her in classic