I bought the least expensive (under $2) 10K 10 turn potentiometers on AliExpress. Wanting to see how long it would last I rotated it full scale idley for a few months while doing other things, it takes around 5 seconds to turn it 10 times, so with the spec on the real ones being 1,000,000 360 degree rotations it would take 138.8 hours of full time twiddling to get to that, I was not counting but 250,000 or so rotations would not be unreasonable. The failure mode was the wire breaking or the wiper breaking, one may have caused the other and I can't be sure which one came first, a brass colored metallic powder was contained in the lubrication.
In my very basic testing at about half way they remained quite linear, but the feel did worsen.
They don't hold up to the real ones, but for the price I was not expecting them to, I would not use them on anything that gets daily use or near their 2W power rating.