The Keystone Vantage line (no longer in production) used the cable system. Open Range uses it on their slides as well. I dont remember what brand of motorhome my grandparents used to have back in the late 80's (or early 90's?), but their slideout used cable system too.
The downside is cables do need routine inspection and occasionally need adjusting; misalignment or being out of adjustment (stretched, etc) can result in a frayed cable that needs replacing. And, if a cable goes or the motor goes out, for many models you have to remove fascia in order to replace or adjust cable and to manually operate the slide.
So far I haven't had any problems with the cable system. My grandparents did have the motor quit on their motorhome's slide and had to remove fascia to operate manually. But, grandparents had a bigger problem and that was my grandmother
At one point (different incident from motor quitting) she let a magazine get under the slide and it eventually jammed things up (got wrapped around the rollers if I remember correctly). Grandfather ended up having to have dealer completely remove slide with forklift to fix it.