PR68DC is VERY high grade for a Franklin. Odds are zero it will stay at PR68DC.
But it will at least be a "real" grade
Instead of just in a somewhat unattractive box.
PCGS tends to be a LOT tougher on DCAM than the other 2, but of course, the reward is significantly more value.
I only use PCGS simply because it is the best and so it's a no-brainer for me. But NGC is reasonable, although lesser.
ANACS is not any more, honestly. They have substantially sold-out, as you can see if you check out the QVC coin collector programs. Even eBay is trying to get rid of ANACS.
If you are planning to hold the coin as part of your collection go PCGS. Selling wise you probably will be around the same if you are patient if you just sell it "as is" or have it certified by another company. Because the market auto-adjusts for the holder type.
Although if it is truly a mirror-heavy DCAM you can use good photos to get the best bang for the buck while it's still in the PCI holder.