Agree with the road noise issue. In addition to front windows, I'm also experiencing road noise from right rear window as soon as car goes above 100kph. Adding air deflectors improved it a little though.I specifically bought RS Sensing variant because I commute on motorway alot but road noise has nullified all the peaceful driving experience I was expecting from adaptive cruise control.
Headunit noise is a known fault. Just stick a small cardboard peice with double tape. Tyres as expected are average at best & should be swapped with contis or michelin.
Flex in metal body parts & plastic parts is completely normal. Crumple zones are much more important than rock solid car.