My bride has been extremely diligent in her dog food contents research and found that the Costco Kirklin Brand is one of the best available. Met a guy upon the Oregon coast who fed his two pooches nothing but raw meat and vegetables and they seemed quite healthy with nice shiny coats. Like I often say "Opinions and YMMV".
As long as you avoid the so called meat by products and a lot of the cereal found in a most of the over the counter stuff your doggie should do just fine. As for the Beano it seems to work well with no ill affects... since we travel in our 25' Class C this is a good thing. :B