I think everyone will have a different opinion on this, but here is mine
My maggie loves her kong too, and I do pretty much the same combo in hers and freeze it so it lasts a while. I do give it to her pretty much every afternoon when she needs something to do (I work from home so this is a good "babysitter"). My vet said it was okay as long as you consider how much she eats for her other meals. I feed maggie in the morning, and then she gets her kong in the afternoon. If for some reason she doesnt have a kong I usually give her another small meal. She seems pretty good with that. She doesnt really get any other treats otherwise. Oh, and she is 7 pounds.