no arch support, that is the point. it's like walking on uneven ground, barefoot, like sand. they're not real cushioned, nor hard and it's more like the muscles in your feet are re-learning how to support your feet while you walk. For some ppl, they're sore for a bit before they are stronger. I have yet to feel sore, but i haven't woren them all too much yet. Have you checked out the site? There is a ton of info on there - or you can call the southyorkshire store (Sheffield). That's where I bought mine and the woman was very knowledgeable (trained and whatnot) and would be happy to answer any of your questions. She even came in while the store is normally closed b/c i wanted to try them on and i was leaving for the states.
As I wear them more, I'll provide more updates on how they feel and if they work. It is a lot to invest, but my brit bf spends just about as much on nike trainers, so I feel it's pretty well justified