I think Tom is ok to point out that this choice was probably suboptimal from a financial perspective. I even wonder if the 6.8% is the proper hurdle/return, since the accrued interest/negative amortization would have gone away after completing PSLF.
Seems like it would be especially tough to beat saving versus prepaying, if you are talking about tax preferred investments versus early retiring the PSLF debt.
Of course, if one decided to make a job change to leave PS, even considering the potential financial benefits, then that's life and you made an informed decision. Sounds like that is what OP did.
