That's an interesting question. The Pacific Coast Highway can be noisy, but not so much that it ever has disturbed us. Even those lower bldgs (1100 etc.) are fairly well back from the road and buffered by trees and the golf course. I can hardly remember hearing a siren. You cannot hear the traffic passing by, just the revving Rolls Royces. LOL. I can't speak for Newport Coast Dr. but again, there are trees buffering most buildings. I would choose 4000, 4100 4200 high floor for view and silence.