Continuum manipulators attract a lot of interests due to their advantageous properties, such as distal dexterity, design compactness, intrinsic compliance for safe interaction with unstructured environments. However, these manipulators sometimes suffer from the lack of enough stiffness while applied in surgical robotic systems. This paper presents an experimental kinestatic comparison between three continuum manipulators, aiming at revealing how structural variations could alter the manipulators' stiffness properties. These variations not only include modifying the arrangements of elastic components, but also include integrating a passive rigid kinematic chain to form a hybrid continuum-rigid manipulator. Results of this paper could contribute to the development of design guidelines for realizing desired stiffness properties of a continuum or hybrid manipulator.