My dog and I both love this product.  It withstands his chewing very well and keeps him involved in safe play options.  The only reason I gave it a four and not a five is because it is either too hard to get items to stay inside or too hard to get them out--it is hard to find that goldilocks zone.  Because there are two large holes on each end, stuff falls out quite easily.  So, to make things stick you have to moisten things or add "sticky" stuff (i.e. peanut butter) to make things stick.  But then it is too hard for the dog to get them out.