I overpronate, I have some troubles with my knees and hips but it's been getting better since I've got support shoes. I run in the Asics 2160s. I've been hearing about people doing some track speedwork in flats. I'm wondering, is it beneficial enough for me to want to do the same? I'm probably going to get hyper speed 4s. But I'm also looking at nike streak XC 2s, saucony kinvaras, nike free run+, and adidas rockets. Thoughts on what shoes or if I should even go for it considering injury. Of course I would work my way slowly into using them.