It's really up to you, it's your dog. Pedigree and Eukanuba and etc are all pretty bad dog foods. I feed my dog Innova Puppy food. Yes, it is expensive, but you end up feeding the pup a lot less than you would have to with crap food. Also, the dog will be much healthier, which to me, means less vet visits!
So it's worth it to me to feed my dog high quality food.