I would like to buy a WMTM wt leggings, but since I can’t return them, I want to choose the one that best fits me first try. My measurements are 27" waist and 37" hips, and according to True Fit, I’m a size 6. But, I wear these old biker shorts from Uniqlo and the size is xs and waist measurement of 24"-25" and it fits well. Also, I prefer to have a more compressive fit around the waist area, but I’ve heard these leggings are already compressive as is? Should I size down to a 4 or keep it at 6?