IMO I don't think that Hills is a low quality food. It is about average for a 'premium' dog food that is available in pet shops in the UK, the kind that most people feed. If your looking at the dog food analysis website, the formula is differant to the one reviewed (one star).
I think Hills gets alot of bad press as it bills itself as 'vets choice' food - see here
http://www.ourdogsonline.com/content/sciencedietscam.html The bottom line is its expensive and bills itself as the best but if you compare it to something newer on the market at a similar price, like taste of the wild-
Salmon, ocean fish meal, sweet potatoes, potatoes, canola oil, salmon meal, smoked salmon, potato fiber, natural flavor, choline chloride, dried chicory root, tomatoes, blueberries, raspberries, yucca schidigera extract, Enterococcus faecium, Lactobacillus casei, Lactobacillus acidophilus, Saccharomyces cerevesiae fermentation solubles, dried Aspergillus oryzae fermentation extract, vitamin E supplement, iron proteinate, zinc proteinate, copper proteinate, ferrous sulfate, zinc sulfate, copper sulfate, potassium iodide, thiamine mononitrate (vitamin B1), manganese proteinate, manganous oxide, ascorbic acid, vitamin A supplement, biotin, calcium pantothenate, manganese sulfate, sodium selenite, pyridoxine hydrochloride (vitamin B6), vitamin B12 supplement, riboflavin (vitamin B2), vitamin D supplement, folic acid.
These are far better products with probiotics and no grains. If you research the web you will find everyone saying that this brand or that food the best, its all down to YOUR dog and its lifestyle, but you as an owner should be aware and informed enough to give it what YOU feel is best.