i love these shoes.  i was skeptical at first and to be honest i haven't had them long but after a few times i do feel a slight difference especially in my core.  my friends, who bought theirs about the same time i purchased mine, also noticed a change in their runs.  i can say that they are comfortable but do feel a little more snug in the lace area than my other athletic shoes.  however i still got them in my regular size as did my friends.  also, i do like the extra cushioning especially in the heel area because it puts a spring in my step.  i would definitely recommend these shoes to any running enthusiast or casual runner!!