with the short ram intake the air has a shorter travel time to the engine where as the cold air intake filter is located under the fender well .this can be good as well as bad. the good part is the air is colder but if u live in where it floods or even hard this can cause water to get into your motor. i recommend that u install a bypass valve if u go with a cold air intake. AEM makes both. also the filter can be a bit of a hassel to clean or replace on the RSX if u dont have a lift. personally i would go with the cold air.