I love wearing tights, they keep my legs warm & since i've started wearing them the excema on my legs has almost completely cleared up, I think it's because irritants can't get to my skin.
As the others have said on here, quality counts.
Also before you put them on give your nails a quick going over with a file to reduce the chance of snags before you've even got them on (very annoying when it happens)
A friend advised that she always takes a spare pair in her handbag in case of a bad snag/ladder & she carries clear nail varnish so if she sees the beginnings of a ladder she can put a dab of nail varnish on it, she says that this stops the ladder getting worse but i've not had the chance to try this theory yet.