First impression of the shoes when I put them on was dang, these things are comfortable; so I thought they were probably the wrong size. The truth is they just have a great fit and a super comfortable liner. They were sized small enough I could do a toe point or edge w/ no slip. Even with a synthetic upper they do stretch some, 1/3 to 1/2 a size. The liner also gets rather slick afterlong days sweating in them. This mixed with the sizing change can be a bit interesting when pulling hard on a heel hook.
Performance has been very good. The rubber is just as sticky if not stickier than C4 and apears to be more durable [them looking good after my bad footwork on Boat Rock's cheese grater rock can attest to that] They edge reasonably well, and once broken in are about as sensative as anasazis. The quick lacing system is nice as it allows for the precition of a lace up with the speed of velcros.
Good all around comfort shoe with a few issues 4/5