Unfortunately there is no one 'best' dog food even within the requirements you have.
Highest quality means different things to different people too.
If you are dealing with a dog that needs to lose weight that would be different than if this diet is chosen because your dog is having problems with the pancreas, diabetes, or bowel incontinence.
Prescription diets such as OM or Hills RD may meet the criteria but may have preservatives or ingredients you don't care for.
You can choose a high protein diet with low fat and add your own fiber.
If you want to home cook recipes from this site on home diets for dogs with pancreatitis may work
http://www.b-naturals.com/newsletter/pancreatitis/
or this for diabetic dogs
http://www.caninediabetes.org/pdorg/home_cooking.htm
You might like for a commercial formula the California Natural food such as this one
http://www.californianaturalpet.com/products/default.asp?panel=ga&id=5
To help keep a dog feeling full you can always add a spoon or two of plain canned pumpkin for the fiber.
Another good quality food that has low fat is Innova
http://www.innovapet.com/product_line.asp?id=1411
This site has some of the best dog food comparison info I've seen
http://www.doberdogs.com/menu.html
giving you info on most of the brands out there including analysis so you can compare if you have a brand in mind.
But you may do best sticking with a veterinary formula if your dog has specific medical issues. Hills RD and WD might work if your dog doesn't like the OM, or Iams Veterinary formula Weight Loss Restricted Calorie food, or Royal Canin Veterinary Diet Caloric Control.
After many years of feeding a variety of dog foods and reading and researching etc. my conclusion is that the best food is the one your dog does best on no matter what anyone might say about the food. The important thing is if your dog is heatlhy, with no skin or gastric problems, is fit not fat, and eats the food happily at every meal.
Please let me know if you have specific questions!
Hoep this helps you!
Dog Expert:Rescue, Train,Breed,Care
30+ yrs dog home vet care & nursing, rescue, behavior&training, responsible show breeding, genetics