Challengers are manufactured as quick-build kits by Quad City Aircraft Corp in Moline, Illinois. In Canada buyers may have their kits professionally assembled for a modest additional charge. The Challenger airframe is pre-built at the factory so even first timers usually take less than 300 hours to complete the assembly, covering and painting of the kit with all available features, options and accessories. No special tools or skills are required.

Challengers come in two-seat and single-seat variants. The two-seaters have full dual controls installed at the factory. The singles exist primarily in the United States where they can qualify under FAR Part 103 to be flown without registration or licence. In Canada all planes are registered and all pilots are licensed so people opt for the flexibility of the two-seaters.

The two-seat Challenger II comes in both long wing and clip wing models. Both are available with wide body or narrow body cabins. Wide bodies have 6 inches more elbow room plus lower cockpit side rails for easier entry and exit. Narrow bodies have high side rails, a sleeker look and less drag. The wide body is favoured by people over 200 lbs or more than 6 ft tall.

The long wing Challenger II has tremendous lifting capacity. It has earned a reputation as being excellent for float and amphibious operations, for ski flying from deep or heavy snow, and for soaring as a motorglider. The long wing's span can be reduced 2 feet by replacing the standard bow wingtips with the optional Hoerner fiberglass tips, thus increasing roll rate and cruise speeds.

The clip wing Challenger II is known as a nimble cross-country cruiser. Its shorter span gives higher speeds and faster roll rates plus a sportier feel.

Over the years the long wing Challenger has been refined to the point where it has substantially closed the speed and roll rate gap with the clip wing. Most Canadians select the long wing with the optional tips for it's greater versatility.