<p>This research paper presents a comparative study of reactionless systems -spring, counterbalances, and redundant actuation- implemented in a decoupled parallel manipulator, which commonly presents mobility issues due to the presence of many passive joints that allow undesired displacements when the actuators are blocked and an external force acts on the end-effector. In contrast to previous studies that mainly concentrated on either dynamic balancing or gravity compensation, the present research combines dynamic and stiffness performance indices to evaluate the influence on motion accuracy and force transmission. The proposed methodology enables a quantitative evaluation of displacement reduction when external loads are acting on the manipulator, with results validated through analytical modeling and finite element simulations. This integrated analysis offers practical guidelines for selecting effective balancing strategies in high-precision robotic tasks such as machining or assembly operations.</p>