Driving impression:
Performance is slightly improved. Less "bog" at startup. Feels smoother and more responsive all around. With hoodliner gone, more of the filter is exposed to air, and some air is allowed to route pretty much unobstructed around the edge of the hood and up and over the driver's side headlight.
I barely notice any extra noise. I hear more stuff, like the "whoosh" of the intake, and some valvetrain clackety clack, but I can't say it's unpleasant. Cruising, it isn't really noticeable.
