I’ve never had a DS 7 but the handbook for the 1st edition shows the petrol THP150 and THP165 both had 6speed EAT gearboxes.
I haven’t seen any video reviews of those cars but have read a report on the diesel that mentioned that the achieved figure was 6.6l/100km, against the ‘claimed’ 4.9l/100km. That’s quite a difference.
I can’t help but wonder if the weight of the vehicle reduces the fuel efficiency.