That is up to you... you don't need one, and Thay don't add any advantage except less noise. Do I use one yes! I'm a construction contractor, around loud noises all day, and I enjoy shooting much more with the moderator than without it. Also, it will help with follow up shots if you are a hunter, it could mean the difference in multiple take downs, or just one and go home. If you shoot in an urban environment, you will want to keep the Noice down for sure. Target back stops can make a lot of noise as well, so you may want to deaden the impact sound there as well. There are many brands to choose. I have only tried one, was happy with the results and see no need to spend the money, instead, I buy more pellets, and go shoot! So, it's up to you, do you need one?