Either are fine, great for underdressing, and delightfully feminine. Why not experiment and see which you prefer, or, wear thigh highs some days and pantyhose on other days. (Not stockings with garter belt or OBG, though—the straps are too noticeable under pants.) I've often done it, but wore men's socks over the hose to protect "my secret." A couple things to consider: pantyhose rule out standing at a urinal to pee, and buy good quality thigh highs that fit you so that they don't end up around your ankles just as you are walking into your boss's office for a meeting. I understand the need. I've underdressed most of my adult life (and I agree with the advice given above about stealth bra-wearing). Nancy