Weirdly, and I might get downvoted, but the IKEA packing cubes (pink & blue set) have lasted me almost 10 years.

Continuous travel - short & long weekend trips, work travel, even used a few for my everyday gym bag in (I pack 1 week's worth of clothes so I don't forget anything in the morning at work). Still use them - except one set is now in my go bag for work travel. I'm really surprised how well it held up, I was originally testing them out to see if it's useful.

The only problem is I don't know if they still carry them because I think they like to discount items like these from time to time.