When my dog was first a pup we used Heartgard chews every month for several years for heartworm prevention. She is a small dog and these were very easy for her to chew and she always thought they were a treat. It was something that she really seemed to always enjoy and it was never a struggle for her to take them. I really enjoyed the fact that these were rather inexpensive compared to some of the other products we eventually switched to. In the end we did switch over to an all-in-one topical product that covered her for fleas, ticks as well as heartworm, because it made more sense to use one product to cover everything. While I do absolutely love Heartgard and my dog loved taking it, I felt that it started to become a pain to have to use this product for heart worm and then another product for fleas,ticks, etc. as well. If Heartgard provided coverage for everything I would definitely switch back, as we loved it and my dog seemed to really enjoy the taste!