This study investigates sub-10nm wide graphene nanoribbon field-effect transistors (GNRFETs) and their performance. All sub-10nm GNRs were found to be semiconducting, with high $I_{on}/I_{off}$ ratios and on-state current densities. The carrier mobility was estimated to be around 200 cm$^2$/Vs, and the scattering mean free path was approximately 10 nm. The sub-10nm GNRFETs were comparable to small diameter carbon nanotube FETs in terms of on-state current density and $I_{on}/I_{off}$ ratio, but offered the advantage of being all-semiconducting devices. The study also discusses the scattering mechanisms by edges, acoustic phonons, and defects, and compares the performance of GNRFETs with carbon nanotube FETs. The results highlight the potential of GNRs as candidates for future nano-electronics, with future work focusing on improving electrostatics and achieving better device performance.This study investigates sub-10nm wide graphene nanoribbon field-effect transistors (GNRFETs) and their performance. All sub-10nm GNRs were found to be semiconducting, with high $I_{on}/I_{off}$ ratios and on-state current densities. The carrier mobility was estimated to be around 200 cm$^2$/Vs, and the scattering mean free path was approximately 10 nm. The sub-10nm GNRFETs were comparable to small diameter carbon nanotube FETs in terms of on-state current density and $I_{on}/I_{off}$ ratio, but offered the advantage of being all-semiconducting devices. The study also discusses the scattering mechanisms by edges, acoustic phonons, and defects, and compares the performance of GNRFETs with carbon nanotube FETs. The results highlight the potential of GNRs as candidates for future nano-electronics, with future work focusing on improving electrostatics and achieving better device performance.