It depends on how soon you are going to train ID and IS. Megyai needs both, Fingal needs just a bit of IS to be better suited.
If you remain in outside training, i'd keep Orav over Hamar as Hamar needs to move into some of his inside areas pretty soon if you are to eventually put him back at a PF type of player. If you do train up secondaries on your guards and eventually switch to inside, then i think Hamar can do far more for you long term.