I have plantar fasciitis and I can wear these just about all day, so they are supportive enough without my orthotics.  I don't think I could wear them every day all day, but I wore them throughout the summer just fine.  They are narrow though, like you need thin feet, mine just fit and I have B/C feet.  If you have thick feet forget it, the strap will be too tight.  The bottom part is quite long like at the toe, for people with super long toes I guess.