I've been 'managing' with a Duzi4 for years (RIP, Cinevate). But as the kit and rigs have grown from a GH5S to a full blown, fully rigged Canon Cinema camera, the slider has become more and more troublesome in terms of rigidity.
So I spent a while researching a new, better more solid one and found Proaim's gorgeously engineered, beautifully designed, rock solid, buttery smooth Flyking.
I've absolutely not looked back, it was well worth the (comparatively modest) investment, and as I got the four foot version I am now blessed with even more travel, all without tilting and dipping at the extreme ends. Also, the friendliness and efficiency of the people at Proaim just make the whole experience even better, shipped and arrived early too.
Fabulous bit of kit, made by nice people. Highly recommended!
Proaim 4ft Flyking Precision Camera Slider (100mm Bowl) (SL-FLKB-02)