Tested the 408 recently. felt the ride was reasonably smooth. Esp at mid-range when u go beyond 60kmph. Fast pick-up with little vibration/noise. Read though that the turbo version which we have here has a slightly 'sportier' suspension compared to the 2.0L non-turbo which AF is not bringing in for local market. Maybe that's why.
Looked through the forum and seems like there aren't any/many 408 owners here. Hmm...