I need to get the dual grips to have smooth walking?  Do dual grips increase the chances of having smooth walking or is shoulder cam the only way?

Hello there, thank you for your interest on the DJI R Twist Grip Dual Handle. Its extensibility allows users to use the gimbal in various configurations. it indeed helps users to better achieve the smooth movements while shooting. For the smooth walking, it also depends on the weights of the camera and the accessories mounted on the gimbal, and the scenarios on the shooting.

Hope this helps, let us know if you still have any questions.