Schwintek=Lippert. Everything they provide is as cheaply made as possible, and replacement parts are overpriced as much as they think they can get away with which is a lot, as most are proprietary. LCI is a big part of the problem when it comes to overall quality in the RV Industry.
On small slides Swlcwintek can be fine as long as the builder made the opening to size and square, used a correct number of bottom rollers, and installed the racks and drive assemblies correctly and in alignment. They get it wrong often.
On a large or heavy slide good luck. Think about it. A 14' long full height kitchen slide that weighs 600 to 800 lbs or more driven by two motors, each smaller than the one in a cordless drill.