It takes 6 months for Ribavrin to be out of your system. Doctors never claim there is any effect of treatment. Not sure exactly why but they don't.
I would post this on the "Hepatitis Coummunity" forum. This forum is for those 6 months past treatment. There would be lots more that have finished treatment on Harvoni. Also, post on the "Cirrhosis of the Liver" forum.
Your right that the results of Harvoni are new. All effects of treatment are relatively unknown. There only appears to be one posting of failure of Harvoni on Medhelp "Hepatitis C Community". Also take a look at the "Hepatitis Social". There is Harvoni post treatment effects on that forum.