Wow...welcome back to YT! Stick around!
Food...oh goodness. I am not like others with ingredients and I only want to say that the food you referred to as "inferior" is similar to a food that has been wonderful for my pup with IBD and MVD (he had liver shunt repaired in 2013). He has been on Hill's ZD since that time and is thriving.
In my mind, if it works don't fix it. My pups eat all the foods that the DFA and others on the web rate as lower grade and they are just fine! My bottom line is that I fear recalls and many of these foods that advertise better ingredients are not doing as much in terms of quality control as they are advertising. (Blue is an example of that) I think ingredients are important but I want the QC as well.