I first got 1 pair maybe 2 years ago and now own 3 pairs (so i got enough for each legday of the week)
While the first pair shows signs of use (from pulling tight kneesleeves over them or getting in contact with the bar knurling) i still use all 3.
I prefer them to other socks for legdays, mainly for the warmth they provide but of course also for protecting my shins from the bar and getting my kneesleeves over my calves with ease.