K&N Cold Air Intake information

Hey guys I am thinking about getting a K&N cold air intake for my 2010 3.5L V6 SXT and wanted to know how many mpg's I can expect to lose. I know that people swear that a CAI will increase mpg's, but I've spoken to many car mechanics, enthusiasts and have read plenty of online articles that state that a CAI will only increase Horsepower and not mpg's because of the IAT sensor that monitors the air temp. So I wanted to hear from anyone with a K&N cai to find out how many miles you have lost with a CAI. Right now I'm doing 385-415 miles per tank and would only consider getting a CAI if the mpg drop is minimal, like around 3-5miles. I don't have any performance modifications and this will be my first if I do decide to get it. Thanks for the info in advance!