New definitions of the Reynolds and power numbers proposed by Farhat, Fradette, and Tanguy (2008) for coaxial mixers were discussed and extended to some other types of multishaft mixers not considered previously. The results confirmed that these new correlations are also applicable for the dual shaft mixer configurations and the Superb lend mixer. This universal applicability allowed the authors to experimentally investigate and compare the power consumption and the mixing time in the coaxial, the dual shaft, and the Superb lend mixers based on uniform criteria. It was found that the Mixel TT-Anchor combination is the most power-efficient combination, whereas the Superb lend mixer requires the most power. Besides, a general approach was introduced to predict the power constant of these multishaft mixers. Finally, the limitations of the new correlations were pointed out through the extension study of their applicability in Superb lend and Rotor Stator-Paravisc dual shaft mixer.