I put them on my v6 that I had for about 2.5 years. I liked them. Good sound outside. If the car sits for a while and it's cold, and u start it up, it's really really loud and deep. Pretty similar to a v8. But at warm idle it's good too.
Interior noise. Let's see, if it's out of the drone range it's a nice little grumble. It does drone in a particular rpm range. Highway does have drone. Just adjust speed to ur liking. I was happy with the kit.