I got these specifically to wear under lightweight sheer beige pants, and they work great. Smoothing effect, no show. My only gripe is that the waistband rolls sometimes.
I am about 5'3", 150 lbs, size 8/10. I got these in C and they fit as expected.
back in the day a young women to be considered dress properly, wore under garment to hold them in plus panty hoes. it seen to be too much. I use to wish for a garment that would control your middle plus have a stocking and when it was too hot wear a sandal. when spanx appeared it was heaven. I thought that was my idea but fail to produce. anyway, they are a perfect for me all year around.