Measurement-wise I need a small, since I'm at the lower end of every measurement, BUT when I ordered the open-toe knee-high socks they ended up scooting down my calf because they were simply too short I'm 5'8". Do you have any experience with these leggings when it comes to longer legs? I don't want to end up with capris...

Due to your height, the small would fit as Capri. In order for these to be long enough for you, you might need a size large for them to be exactly on your ankle bone.
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