I've fed Taste of The Wild, Blue Buff, Solid Gold- wolf king, Wellness, Iams, Nutro, California Naturals.. the list goes on.
Orijen, or Wellness Core is my vote.. However, they are both hard to find depending on your area, and expensive.
I am also a firm believer in a B.A.R.F or RAW diet. I have 4 pitbulls, and when they were on raw they did amazing well, and looked amazing. It however became costly. haha.