I've loved Kayanos, but with every change, they seem to fit my feet less and less.  I have long, narrow feet that over-pronate and generally need lots of cushion and arch support.  The 22s were perfect, except that the toe box was way too narrow.  The toe box is a bit wider in the 23s, but not wide enough.  I have very narrow feet, but I ordered the B width shoe.  The toe box fits me perfectly, but the heel is to wide.  Also, the are uncomfortable to wear for an extended period of time because they don't provide enough cushion for my feet.  I usually wear size 11 but I always have to order size 12 in ASICS.  The length was actually as expected--but the width of the toe box was still too narrow.