I'm looking at the two systems RJC sells and am leaning toward the 4 inch set up. I have listened to the sound clips on their site and don't mind the 4 inch. Was curious what people that were running this set up or are familiar with it thought about it as far as "real life sound" idling and WOT, as well as look and fitment. Please let me know your thoughts and/or experiences with it or even the 3 inch....