I purchased the car used and it came with the Z1 single exhaust. It sounds great and all but due to my neighborhood, I cannot have it that loud. So I decided to get the HKS exhaust (real ones, not fake). I had 1 on my g35 coupe before and I loved the sound so I decided to get one for the 350Z.

Here's the install video with some sound clips at the end of the video. If you want to hear the Z1 sound clip, it's the very first video in my channel