I think it's best to find a brand your dogs like and you can afford and stick with it, unless you have to make a change. Recent cost increases have forced a lot of people to reconsider what they were feeding. I don't like changing dog food but I have Vizsla's and I have found them to be a pain in the butt when it comes to what they like to eat. Most of the people that I know...ie: breeders, trainers and people that compete in trials and hunt tests feed the best they can afford but don't change brands/food often. Pro Plan and Inukshuk are really well thought of but there are several others that dogs seem to do fine on. Inukshuk is really dense and high calorie feed....even more than PPP. I was getting it for $50 a bag from a re-seller and is a really good value. You will fed less of it than PPP or others too. Eukanuba is more expensive than the others mentioned and I don't know any that feed it except for a well known kennel in Kansas that is sponsored by them. A friend of mine breeds GSP's and trains dogs and she has switched off Pro Plan to Valu-Pak 24-20 because of cost. Diamond is available just about everywhere too and they make food for Sam's, Costco etc.,
I went from Pro Plan to Inukshuk to Nutrisource. I don't know a lot of people that feed Nutrisource, but I was running out of options that I can get locally or on the road and Inukshuk wasn't working for my Vizsla. Nutrisource costs me about $70 for a 40 lb bag.