I just went to Fuk for 1 week self-drive. There were 6 of us in a Serena. Seating is very comfortble but it has limited luggage space. We are able to fit 2 medium size Samsonite and a large semi-soft bag on top, which partially block the rear view. Under the floor of the cargo space there is a secret compartment which is big enough to store a carry on bag.
If you are renting from Nissan, they'll give you an E-hybrid, which is OK with regards to power and gas mileage.