In this paper, two redundant controllers are proposed in order to boost the capabilities of the popular feedback linearization flight controller scheme. The first one is based on the sliding mode framework whilst the second one is built upon the Model Free Control (MFC) theory. An in-depth discussion is highlighted with detailed evaluation in terms of performance, consumed energy, and robustness by considering several scenarios and using several metrics. The numerical simulations have shown satisfactory results using nominal system model or disturbed model through an application to a small Vertical Take-Off and Landing (VTOL) quadrotor.