I've never been pulled over- and even if I am pulled over, the chances they will check the under the hood are very slim- unless they heard me giving it a go or caught me speeding.

Mines lowered by an inch and a half, and has 19s. You dont hear the CAI unless you want to hear it i.e. when you floor it. Just commuting to work etc. at the speed limit and the speed of traffic- you dont hear anything.