[relic]

wind noise with roof fully retracted is probably to be expected

I have no window noise at all - have just been cruising at 75 mph for over an hour with no extraneous noises

suggest subtle steering wheel vibration is either Lane Departure Warning or Active Blind Spot Detection - unless you don't have them

no sign of engine noise on 550 but I have had the tranny-slam a couple of times in heavy traffic

overall very impressed with GT although still only 300 miles on the clock!