Well, personally, I think if you're feeding Wilderness, they have to be a very high-energy dog that gets a lot of exercise in order to work off the high number of protein and fat levels they are in taking. Also, Wilderness is NOT grain-free. It contains good grains though. Not all grains are bad, by any means. It all depends on the dog really. Some dogs do fine with grains but a common allergen in dogs is corn, soy and wheat. I would stay away from those as well as by-products.
I actually just started working for Blue Buffalo, and the biggest complaint is that the dog won't eat the Life Source Bits. Those bits are really an added layer of protection so they're not required for nutritional value, it just gives them extra, basically. However, it's like a child eating vitamins... they're going to spit them out. Eventually they usually will begin to eat them. However, even though I work for them (lol) I do not feed Blue Buffalo. I think there IS better food out there, however if you
must shop at a Petsmart for dog food, Blue Buffalo is the way to go. It's probably
the highest quality food you will find at a store like that.
High protein levels can also depend on the health of a dog. If a dog already has kidney or liver issues, high protein is not good. There's many debates on what is too much and what is too little. Personally, I wouldn't feed anything less than 22% or anything higher than 34%.
The grain-free arguments are that a dog is supposed to eat like they would in the while, which I sort of believe in. However, the other side is that if a wolf in the wild is eating an animal they killed, the animal are they eating (such as a rabbit for example) would have eaten grains, therefore the dog DOES take in some grains from their stomaches, etc. If that makes any sense.
Jackson eats Innova and LOVES it. I think the ingredients are wonderful and the company seems very good and reliable. I really love the company. They also sell EVO and California Natural. Wellness is a really good company too though. I think it all depends on the dog and what you're comfortable with.
I think the MAIN thing to look for in a dog food is a NAMED MEAT product as the FIRST ingredient. It's even better if a meat is named as second and/or third as well. No by-products, no corn, no soy and no wheat. This is just my opinion but I think this last paragraph here most people on this site will agree with.