If you are training then put a handful of regular small dog bikkies in your pocket.Do this when he is hungry and the results will happen faster than if he already had a full tummy.You can get small marrowbones and hard crunchy bars from the supermarket as treats for them to munch on for ages. It is trial and error with the products and depends on the age and size of the dog.These products are not designed for training ,they are to keep your dogs teeth clean and amuse for hours.There is no need to go for the expensive brand.If it is too big for the dog to eat in a day then it could bring in the ants and if it is small and gets eaten in a few seconds then try for something different.