The fabric is sturdy. As the waistline is ribbed and I have a short waist it tends to fold down, but I think that is true of any high waisted legging for me. They are a bit on the tight side even though I am a true UK 10-12, so a fair amount of compression, but I suspect that will relax a little over time.
I adore these, the fit is perfect, I'm usually an 8-10 so small fits me perfectly, not too snug. Very flattering and love the flower detail.