Great toy in theory, buy my dog (8 month old weimaraner) won't play with it.  I've even tried rubbing peanut butter on it, he just licks it off.  I originally got him this toy when he was 4 months old and though he would eventually grow to like it as he become a stronger chewer, but no.  He prefers pig ears, pizzle (bully sticks), rawhides, and the rubber used to make Kongs and the like.  YMMV