They reposition your footpegs. Higher and further back for better ground clearance when leaning. In addition the footpegs are fixed and don't fold like the stockers. In the event of a fall they work almost like sliders.
i would say that satos are a track favourite among our customers. you can call us to order vortex, sato, woodcraft, or gilles... among others. i'll be glad to explain the differences over the phone with you.