What ever I used both full contact and had no problem. Cochranes are not toys by the way you can jam them, pound them, will not break. Been there done that. Ritter steel we use in are full contact traning never had a problem. So this is from on the job training. One other thing any time you pick up a sword you are training if its extreme or full contact. Most Japanese arts dont make contact only with wood swords or bamboo not very real but to each his owne.