I've used cheap Sunlite brake cable housing for some projects. The stuff compresses for awhile so I had to adjust the brakes often. After several rides it settles in and stays put. Next time I'll get some decent compressionless brake cable housing from Jagwire or Shimano.

I've read claims that cables don't stretch but I'd swear the cheaper stainless cables I've used did stretch. I'd need to measure to be sure. But even in shifter applications, where housing compression wasn't a factor at all, I've had to adjust cable tension several times until the cables settled in.

I haven't had any catastrophic failures of cables or housings with cheaper stuff. No unusual friction or other performance problems. Just some apparent compression with the housing and stretch with the cables.

FWIW, even the cheapest Shimano stuff that comes with entry level RevoShift grip shifters and SunRace SLM10 thumb shifters seem to work better -- less cable housing compression, no apparent cable stretch.