I think you will be happy with Solid Gold, it is a very decent brand and leaps and bounds above IAMS.
Instead of looking at the stars, I prefer this site:
Dog Food Ratings by Brand
Many dog foods are rated low on the site that rates by stars because they have less protein but for these small dogs that is not a "bad" thing and is actually necessary for some.
The site I linked will tell you if there are any controversial ingredients in the food you are feeding and what the controversy is.
Dont be too concerned if you see a red ingredient (there is one in the food I feed too!) just read why it is controversial.