I really don't get it. There are a bunch of shoes within the same brand, that seemingly serve the same purpose(everyday trainers). How to decide which one to get? How would the shoes in the title compare to my current shoe, the Winflo 6? The reviews on different sites say nothing of substances, and the official site of Nike is no different Also, I only have enough money for one shoe at a time, and I have to use it until I have near 1000 miles in the pair. Does this negatively impact my performance?