The engine note is quite harsh at revs but not that bad. It sounds much better when you get rid of the standard exhaust.
The tyre noise isn't that bad. It's not whisper quiet but not intrusive.
The 370 is a great car, looks brilliant, handles well and goes like stink.
It is a pefect tourer if you can fit enough luggage in.
Go for it, you won't regret it.