I bought Perto boots, size 37. I thought they would be smaller, from the sizing guide I tested, but they are a bit more long than I thought. Anyways, I kept them because 36 will probably fit too short. The sole are thinner than other barefoot shoes and it's not even - some parts of the sole doesn't have rigid part, which I think it's weird, specially in winter boots, and you can actually feel the irregularities of the sole itself when you walk - I don't know if that's the idea, but I'm used to barefoot shoes where you can't feel the sole. The insole are non removable and I tried to buy another insole to add extra protection for winter, but they were not available (I'll try to sew ones myself). They are warm, easy to walk and very light-weighted.