There are several topics we have had over the year about dog food, I personally love to talk about it and learn about different ones and try some of them.
I have found it is more beneficial to feed the better brands. They consume less and their output is less. If you feed Pedigree(which I used also) there was more output. When I fed Royal Canin or Professional there was less.
Shaianne was an 80 lb greyhound who ate a half of a SMALL can of food or 1/2 c bil jac frozen mixed with her Royal Canin. She had small output. When she was on a cheaper brand when I spent the week at my parents, my dad was totally flipping out b/c there were like 20 piles around 'tree'!!