I wear these as a pettipant slip, over my underwear, when I wear skirts and dresses.  I size up (from the hip measurement size) so they fit more loosely.  They don't ride up as much when they aren't as snug and do a good job protecting against chin rub, and they are cool (especially when loose) and don't make me sweaty.  The waistband is a bit snug for the sizing, but stretches out a lot.  It cuts in a bit if I don't size up, but loose is perfect for my needs.  I am back today to get a size bigger because I am pregnant and need a looser fit in the waist and wear shift dresses to work.  The 4x work well right now (I wear an 18 in pants, for size perspective) but I am getting some in 5x to accomodate more in the belly as it grows.