I have been running in Zoom Fly shoes for some of my faster tempo runs. (the originals, not flyknit) I like most things about them, but the heel cup is so stiff and high that it causes chafing on the back of my ankle / achilles. Even through socks. I can't run more than about 6 miles without getting blisters where they rub. The only solution is bandaids, but they tend to fall off if I run far enough.
1. Does anyone else have this issue?
2. How about the Flyknits? Did they fix this issue in the new shoe?