It might be a bad idea to use OJ to mask the 4-FA. When I used to take Adderall IR in the morning I noticed it was useless if I took it after eating a breakfast with OJ or anything acidic. Do a search, you'll find a lot of stuff about adderall and acidic stomach/bladder. Personally, I eat a pair of antacids a few minutes before dosing.
Of course the extra Fluorine molecule might change everything, but stomach acidity is probably something to pay attention to.