Depends on your scenario. If I had them I would keep them and save the $140 on my next set of MYW tickets by skipping the hopping option.
I would (again in my situation) buy MYW non hoppers (preferrably 10 day to use over 2 trips) We only hop a couple of times per trip. So with your tickets I would do a 7 day trip hopping 2 of the days and a 6 day trip in the future hopping 1 day.
If you are taking a shorter trip you could do 3 day exp, non hopper and use the other 3 days to hop, BUT that may not be a good deal... OK just looked it up: A 3 day ticket would be $182, and a six day would only be $208. So I'm not sure how they do the math, but surely the credit for the 3 days would be worth more than the additional cost of $26 from buying the 6 day ticket, even if you add the $35 to hop all 6 days it seems like you'd have to come out ahead trading up.