J.B.
In my experience, enforcement is best handled by the state in which the support-paying parent resides. If that's SC, then leave the order there. If you move it to PA but still need SC involved, then you have to go through the step of setting up a UIFSA (Uniform Interstate Family Support Act) order so that SC can enforce the order on behalf of the state of PA.
If the father is in NC or some other state, then you already have a UIFSA in place and it may make sense to move the order to PA. If that's the case, ask the lawyer who mentioned it to you what she or he perceives the benefit to be. There are questions of jurisdiction with interstate orders so that's why it may make sense to move it to PA - that way, PA has jurisdiction over the order and you can request modifications, via the state in which you actually live. Of course of the guidelines in PA are less favorable to you than in SC, it may make sense to let sleeping dogs lie.