It's purely choice. If you want to hear the intake more and like the throttle response, then leave your hai/cai/sri on. It isn't hurting anything, but you are adding a mod that is not needed at your power level... And mostly all cars out there.
Barely anyone gets to that power level where a new intake is needed. But hey, it's a fun, cheap mod to do (depending if you buy or build one) and it sounds cool.
I made one, I thought it was sweet and it is. Who wouldn't want that throaty sound?