hi I have also just got SAIS for this year in Bologna and another in DC.
ANd I also Applied to UK too. But what I see is SAIS is better than UK if you are interested in working in IR field. But if you wish to continue studying IR till Phd then Oxford is better.
I think I am also in same situation like you as I am also a foreigner and JHU has limited reputaion other than US. But I think that doesn't matter after all people in IR field know that SAIS is the best.
Hope to meet u in Bologna.