I think there were a few people who were on the fence between getting more 5s or trying the 6s. They are clearly different from the Ghost 5s, but, for me anyway, not in a bad way. They seem to fit my foot the same way and I haven't developed any weird pains or injuries from running in them. The sole looks a lot different to me, but they don't seem to behave much different. I'm quite happy with them so far.