This funding has enabled them to precisely simulate their designs and performed experiments. They have stated they would need $100 million and five years to actually make a full megawatt propulsion system. They have not received the level of funding needed to proceed with the main development.
Studies of electron heating in PFRC-2 surpassed theoretical predictions and recently reaching 500 eV with pulse lengths of 300 ms, and experiments to measure ion heating with input power up to 200 kW are ongoing. When scaled up to achieve fusion parameters, PFRC would result in a 4-8 m long, 1.5 m diameter reactor producing 1 to 10 MW.
They have published various journal papers that review their computer models and simulations of the system. The Direct Fusion Drive concept is an extension of ongoing fusion research at Princeton Plasma Physics Laboratory dating to 2002.
The NASA NIAC project included analysis of the following subsystems: the superconducting coils, heat extraction system, startup system, radiators, and shielding.
Direct Fusion Drive (DFD) would produce between 5-10 Newtons thrust per each MW of generated fusion power, with a specific impulse (Isp) of about 10,000 seconds (chemical is 300-400ISP) and 200 kW available as electrical power. These would be first-generation capabilities.