Jimmy is right. The Apexi N1 is very loud ( I have one on my 240). However, if you get the active tail silencer it's not to bad. The nice thing is that when you drive normally it's pretty quiet, and when you give it, the valve opens and let's more exhaust out (more noise too).
A'PEXi U.S.A. - Products: Exhaust
Here is a pic of it on my 240.
