The cable system makes me shudder when I think back to rethreading cables on my Starcraft popup years ago, but I really don't have any experience with them.
What I do have experience with is Schwintek (rack and pinion as you call it) on our forward slide and it is not great either. I have to keep it lubed, or it shuts off before the slide is actually closed, and it just sounds fragile. I'll take hydraulic anytime, but I understand with the new front living rooms and taller slides it is not always reasonable to install a hyraulic piston under the slide.