I just started my Invisilign treatment 3 days ago. They do hurt some when you take them out and put them back in after eating, but I can feel my teeth moving already and that's exciting. My treatment is almost an express case, the bottom teeth will be completely fixed in 2.5 months and the top ones in 7 months. Yesterday I asked my dentist to show me the very last tray, and that got me very excited since it looks exactly like what the 3D animation shows at the end, no more crowding and gap is gone!