Go with the 90mm. In test after test that I've seen, the 90mm makes more power when its mated to an intake that supports that size, like the TFS-R Box Upper.
I personally believe the narrative that flow with forced induction is substantially different than without is false. If a part flows more at a given atmospheric pressure, it'll also flow more at higher pressure. The only exceptions are when you're timing valves, hitting velocity limits, or doing resonance tuning, none of which applies to TB size selection.