If you believe the "experts", meat should be the first ingredient which is not the case of the Trophy adult food you mention. I know Trophy do a dry food where meat is the primary ingredient because my in-laws feed their dog on it. You should also avoid foods that contain fillers that have no nutritional benefit i.e. corn (maize). Maize is third on the list so it is probably quite a high percentage of the food. Rice and potatoes seem to be considered ok because they are a good source of vitamins and minerals that are nutrionally beneficial for dogs.
There is so much conflicting information out there, there seems to be no definite answer and lots of differing opinions. Just remember that dogs are carnivores so meat would be their primary food group in the wild.
I would go with the best food you can afford, remembering that just because it is expensive doesn't neccessarily mean it is the best quality. Check out
Dog Food Reviews - Main Index - Powered by ReviewPost for more information. I used this site as the basis for further research. I decided on Orijen and fingers crossed, my puppy is doing very well.
Adam