I started off with Mudclaws, and on my first 10m race out of the box they were fine. Infact they were great for 4 or 5 races and then one day I blistered badly despite have duct taped my feet (for my ankle, not the sole). From that day on I blistered the same place every time out. I bought some Walsh PB Ultras and they were fine on short races but anything long with wet feet, blistered again. Then some good advice,
see here, zinc oxide tape, I now tape for anything over about 4 miles when I know my feet will be wet or anything long, 10 miles or more just in case. No blisters since with either the Innov8's or the Walshes.