As far as construction & materials, there isn't much difference at all between the men's Nike Flex Run shoe and the men's Nike Free Run series. Both have a sculpted Phylite™ midsole/outsole which provides support and cushioning, both have a no sew forefoot upper construction, all designs use the Deep Nike Free sipes in the outsole for a barefoot-like feel, and all have a light weight for a great performance running shoe. Your decision may become dependent upon the actual look & design of each style rather than the construction because they are all so similar in this area.
answered 1 year, 1 month ago
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