All of this reminds me of the CAI vs Stock Airbox discussions in the VW/AUDI world from about 10 years ago when they introduced the 1.8T (Nevah' Loose) engine.
I've been saying this for a while now, but I'll repeat it again: the best flowing intake would be gutted and smoothed out stock air box with drop-in performance filter.
Dinan intake and Mr.5's intake mod are also excellent solutions as well!