This is my 5th pair of Vibram 5finger shoes. I typically love these things and Ive never had this particular issue. As others have stated there is some sort of defect in the manufacturing and with how it was put together. The rubber on the big toe intrudes inside and rubs your toe. I cant break it in and it just rubs my toe. VERY annoying. cant even wear them for walking let alone running. The shoe itself is light and breathable but the seam issue is a HUGE issue.