340i was far too quiet for my liking. Had burbles on the overrun and if you blipped it at idle. Gave the aforementioned 'WHumphfff' when changing up with more than say 50% throttle, and on a very rare occasion(not often enough for me) it'd give off a unshot. When i say rare, I mean i had it for 24k miles, and it did it twice.
now have an XJ6N with a titanium exhaust system which is lovely and loud. I do keep it as quiet as i can when I go to/come back from work at 0615, and 2315, but in the middle of the day it sounds glorious! It burbles on the overrun, though I don't think loud at all, and does let off a deep bang when the exhaust is cold and you let the revs drop through 4.5k rpm
Yes, yes I am a chav