Purchased a pair of underwear that was both uncomfortable and way too big - I wear a medium from every other brand and store, but the medium from Knix was about 2 inches wider! In terms of the period-proof aspect, they're just as uncomfortable as wearing a heavy pad, and too loose to be leak-proof. As many others have mentioned, there is a no-return and no-refund policy, which is frustrating for such an expensive item. I left a 2-star review on the site, with a photo attached displaying the Knix garment next to a standard medium for size comparison. The site never published my review! In fact, I scrolled through and there are only 4 and 5 star reviews on the site. Dishonest!