I'm sure they do, perhaps they would do better in casual dress shoes. I need some for my cross trainers since I teach aerobics 4 days per week...I was thinking more along the lines of polypropylene since they are very strong yet have more flexibility than graphite and polyethylene.
I really don't have the money to spend on those right now and I think they'd need to make a few modifications as I also have minor gastroc-soleal equinus and a flexible flatfoot that has been rather asymptomatic as of late. Sometimes my plantar fasciitis presents on one foot for a week while the other is pain free and vice versa.
Any suggestions as to where I can get some functionals for cheaper prices than $300?