Quality - Amazing, thick, smooth, high compression
Sizing - If you have thick legs or curves, DEF size up 2x. The large fits me well for the other leggings series, but this one I wish I ordered an XL just in case because now. . . . I don't see a point in returning them since I'd be losing money.
Reference: USA I'm a medium, so I assumed large would fit well, which it did for their other their other leggings, but not the 380N :(