Sorry, what action are you referring to when you mean Rangers' Flurry? And what Feat you are getting from it
I'm going to guess whatever action it is, however, that it probably has Flourish on it - which Monk's Flurry of Blows also has, so you can't use them in the same round.
But, the build could still work. You would be getting around a Monk's disadvantage with Flurry of Blows, and could probably get three attacks in one turn without suffering too much from MAP (particularly at higher levels) against your Hunted Prey. That does sound strong for the right build and character concept.