Ok this is for hard-fast V6 owners but my interest in my Lady has just been renewed.
Gone are the imported K&N, the heat shield and custom made heat wall, in their place a Courtenay large inlet box and a K&N flat panel, connected to the three-pipe mod.
Gone is the exhaust noise I thought was normal for the modifed cat-back rear twin pipes and turned out to be a split + loose baffle in the center box.
I live not far from the M4 and just got back from a little drive.
What I have now is a Lady that effortlessly reaches motorway speeds and more, even around town and I don't know she doing it, ok the GPS beeps but I am now having to look at the speedo as I am not aware of the speed she is doing.
I notice the tell-tale wind noise you get when passing cars or seeing them disappear in the rear-view mirror and the exhaust tone is deeper, other than that no induction whistle

just pure quiet power.
Gear change I notice is also different smoother , 7,000 rpm is not an effort in any gear ( my comparison with fords lol) and there's no engine strain noise.