One-of-a-kind experience. Flying fun, simply stated.
Why? Because the graphics are superb for a game from '96, the controls are realistic, and the gameplay is challenging and engaging. More on each starting...now:
The controls can be frustrating at first, because only the rocket pack seems to do what you want when you want. The hangglider at first seems to know only one direction (DOWN!) and the 'copter is slow to change directions. But think about these two vehicles and how they move realistically. Both are more or less at the mercy of the wind and air resistance due to their low density. For this, one must patiently learn the intricacies of steering both before they can be enjoyed fully.
The missions are all mostly target based, flying through rings, shooting targets, and proper landings, sometimes timed. Really, the fun for me was thoroughly exploring the levels during these missions. The mini-USA is quite a creation.
Sky diving and Cannon are both extra modes that are earned after completing so many missions. The missions for the first involve completing formations during a free fall and then parachuting onto a target. For the cannon, your character is fired at a large target that is only hit with the proper trajectory, velocity, and consideration of wind.
If you still own an N64 but have never played Pilotwings, go pick it up at one-tenth what I paid.