The first time I used a Nikon D4 I thought how it was so comfortable in one hand...well balanced that you can keep it (with lens) suspended with one finger. ....and what about performances? Don't try it if you can't buy it ! It's a master class camera for sport and action photography. The AF is simply superb and very fast in every condition. Colours are very natural and deep at the same time. Each button and wheel is in the best position to be used without removing your finger from the shutter button. The camera can be used in all hard weather conditions without fear of dust, rain and mud.
My verdict:
Lightness: 10 (for its self-balance with lens mounted)
AF speed: 9
AF accuracy: 9
Utility: 7 (because it's bit an all-round camera)
Benefits: 9
Price: 9 (a bargain if bought second handed with not too many shutters)
Global rating: 8,8