Bought a few pairs.  On one, the silicon rubber was already so bad they would not stay up.  On the others, it got flabby within 3 or 4 wearings.  But, that's not so bad... since they are so ridiculously thin and run so easily (I put socks over my nails when putting them on, so no, that's not it).  These are really disposable 1 use stockings.  Blech.