My mom bought my backpack 25 years ago and the clerk told her "they'll last for at least five years".
Well I still use mine daily, so yeah. Definitely lived up to expectations. Although I've did get it fixed, but first time just a year or two ago. So lasted without any fixing for longer than the average age on Lemmy, I'd say.
I bought a laptop backpack a loooooooong time ago, and still use it constantly. It's been through 3 laptops, and I'm not the type to upgrade until it is absolutely necessary.
I bought a military grade backpack on a Marine Corps base in 2001. I used it for 3 years in the military, then all of undergrad, masters, and phd school. I use it on almost all of my travels, and I use it daily in town. It's still going strong. Hope to get another 23 years out of it.