Performance
The M56 is a quick car, especially considering its weight. Power is soft below 3,000 rpm, but then its V8 revs very hard to the 6,700-rpm redline. 7-speed transmission shifts quickly; paddle shifters benefit for performance driving.
Driving Dynamics
Variable assist steering is too quick at low speeds; becomes more natural at higher ones. Stiff suspension gives excellent handling until the road gets bumpy. Will oversteer with drop throttle. Very good braking numbers and pedal feel.
Ride Comfort
Due to the Sport package the M56 has a stiffer ride than most in the luxury sport sedan category. It's fine on smooth highways, but its harshness over bumps may 'shock' some customers.
Quietness
The M56 has a very quiet cabin. Wind noise is near nonexistent at normal driving speeds, despite oversize mirrors. There is some tire noise on certain surfaces due to the Bridgestone summer tires.
Ergonomics
Comfortable front seats, although not particularly supportive laterally considering they are the optional sport seats. Seating position is a bit high, even in lowest setting. Controls within easy reach. Rear seat is exceptionally plush.
Visibility
Rear/side outward vision is marred by a high tail and a thick C-pillar; small window in the C-pillar helps marginally. The rear camera takes away the guesswork of backing up, though. Front outward vision is very good.
Seat Access & Space
Easy to get in and out of the seats, front and rear. Headroom could be tight for people with long torsos front and rear, as you sit rather high in both areas.
Cargo & Storage
The trunk is a good size, wide although not particularly deep. Unfortunately, split-folding rear seats are not available to increase the loading capability.
Build Quality
The leather interior is soft and expensive-feeling; the real wood trim has a deep, lustrous appearance and is classy. Only on a couple of trim pieces did it seem like Infiniti skimped. Overall, the car is very well made.
