I have two cats and they both love these treats. I open the bag and they come running and they will eat every last one I give them. I've tried other treats with them and either one cat likes it the other doesn't or neither cat likes it. My cats have also gotten bored with other treats before as well, never with their greenies! I gave a bag to one of my friends once for her cat and I know that she now keeps them stocked in her house as well. The back of the bag tells you how many treats to give for dental hygiene but since I don't really use these for that, I don't follow it. To be honest though, I probably end up giving enough throughout the day anyhow just as treats. :)
I do use a dental powder that gets sprinkled in their food so I can't really speak to any dental benefits this treat may have. While I don't know if I would recommend relying only on this for your pet's dental health I figure every little bit helps, right? Overall, if my cats could talk, they would give their greenies a million stars. (Oven Roasted Chicken is their favorite, favorite).

Pros: Cats Love them, supposed dental health

Cons: Pricy considering how many you have to feed for dental health