1. Yes I have to wear one, I dont want them slapping me in the face when I go down stairs.
2. Kohls, they have good sales
3. around $30, they dont really give me all the support I need though
4. My size changes a lot because my weight changes, so I keep them until they don't fit. I have one that I think is ready to retire though. its over a year old
5. yes a I have a favorite. its the one that pushes me up the highest