As mentioned, different dogs will each do differently on different feed, based on each dogs' life style. i've based my decision, primarliy on two things: nutritional canine needs and the standards set by AAFCO.
one, you will find here: http://www.peteducation.com/article.cfm?c=2+1659+1661&aid=662
and on the nutritional needs of my dogs, which i've included, and you will find here: http://dels.nas.edu/dels/rpt_briefs/dog_nutrition_final.pdf (lengthy read, but imo, worth it.)
i feed some raw, primarily chicken and beef along with (approx) 1 c kibble twice a day. i mix a combo of Evo and Canidae. Evo because it's a better (imo) product, but pricey, hence it's mixed with the Canidae. My dogs are hand walked 2x a day, approx 3-5 miles each time and they are run for 45 min each night.
i don't supplement because the following:
Protein.........18%
Fat..............5%
Calcium......0.6% (maximum 2.5%)
Phosphorus...0.5% (maximum 1.6%)
Potassium.....0.6%
Sodium........0.06%
Chloride.......0.09%
Magnesium.....0.04% (maximum 0.3%)
Iron............80 mg/kg (maximum 3,000 mg/kg)
Copper.........7.3 mg/kg (maximum 250 mg/kg)
Manganese........5 mg/kg
Zinc...........120 mg/kg (maximum 1000 mg/kg)
Iodine.........1.5 mg/kg (maximum 50 mg/kg)
Selenium......0.11 mg/kg (maximum 2 mg/kg)
Vitamin A.....5000 IU/kg (maximum 250,000 IU/kg)
Vitamin D......500 IU/kg (maximum 5000 IU/kg)
Vitamin E.......50 IU/kg (maximum 1000 IU/kg)
Thiamine.........1 mg/kg
Riboflavin.....2.2 mg/kg
Pantothenic Acid..10 mg/kg
Niacin..........11.4 mg/kg
Pyridoxine.........1 mg/kg
Folic Acid......0.18 mg/kg
Vitamin B12.....0.022 mg/kg
Choline.........1200 mg/kg
yup set by AAFCO (*amounts listed are MINIMUM requirements)are met with their feed. (see below, as an example of Canidae).
As Fed Dry Matter Energy Basis
Moisture 8.5 %
Protein 24.2 % 26.4 % 6.8 g/100 kcals
Fat 14.5 % 15.8 % 4.1 g/100 kcals
Omega-6 Fatty Acids 4.03 % 4.37 % 1.12 g/100 kcals
Omega-3 Fatty Acids 0.5 % 0.5 % 0.1 g/100 kcals
Ash 8.0 % 8.7 % 2.3 g/100 kcals
Fiber 4.0 % 4.4 % 0.99 g/100 kcals
Carbohydrate 39.9 % 43.6 % 11.3 g/100 kcals
Arginine 1.39 % 1.5 % 0.39 g/100 kcals
Histidine 0.53 % 0.6 % 0.15 g/100 kcals
Isoleucine 0.87 % 0.9 % 0.24 g/100 kcals
Leucine 1.69 % 1.8 % 0.48 g/100 kcals
Lysine 1.14 % 1.2 % 0.32 g/100 kcals
Methionine Cystine 0.85 % 0.9 % 0.24 g/100 kcals
Phenylalanine-Tyrosine 1.59 % 1.7 % 0.45 g/100 kcals
Threonine 0.89 % 1.0 % 0.25 g/100 kcals
Tryptophan 0.21 % 0.2 % 0.06 g/100 kcals
Valine 1.09 % 1.2 % 0.31 g/100 kcals
Calcium 1.80 % 2.0 % 0.51 g/100 kcals
Phosphorus 1.20 % 1.3 % 0.34 g/100 kcals
Magnesium 0.16 % 0.17 % 45 mg/100 kcals
Sodium 0.17 % 0.19 % 0.05 g/100 kcals
Potassium 0.65 % 0.71 % 0.18 g/100 kcals
Chloride 0.45 % 0.49 % 0.13 g/100 kcals
Copper 11 mg/kg 12.25 mg/kg 0.37 mg/100 kcals
Iron 300 mg/kg 328 mg/kg 7.5 mg/100 kcals
Manganese 25 mg/kg 27 mg/kg 0.7 mg/100 kcals
Zinc 200 mg/kg 219 mg/kg 5.0 mg/100 kcals
Iodine 2.5 mg/kg 2.7 mg/kg 0.1 mg/100 kcals
Selenium 0.20 mg/kg 0.22 mg/kg 0.006 mg/100 kcals
Vitamin A 15,000 IU/kg 16,393 IU/kg 423 mg/100 kcals
Vitamin C 50 mg/kg 55 mg/kg 1.4 mg/100 kcals
Vitamin D 1,000 IU/kg 1,093 IU/kg 28 mg/100 kcals
Vitamin E 200 IU/kg 219 IU/kg 5.6 mg/100 kcals
Thiamine (B1) 40 mg/kg 44 mg/kg 1.13 mg/100 kcals
Riboflavin (B2) 8.0 mg/kg 8.7 mg/kg 0.23 mg/100 kcals
Pyridoxine (B6) 13.0 mg/kg 14.2 mg/kg 0.37 mg/100 kcals
B12 0.14 mg/kg 0.15 mg/kg 3.9 mcg/100 kcals
Beta Carotene 5.75 mg/kg 6.28 mg/kg 0.16 mg/100 kcals
Folic Acid 2.0 mg/kg 2.2 mg/kg 0.06 mg/100 kcals
Niacin 66 mg/kg 72 mg/kg 1.9 mg/100 kcals
Pantothenic Acid 25.0 mg/kg 27.3 mg/kg 0.71 mg/100 kcals
Biotin 0.33 mg/kg 0.36 mg/kg 0.01 mg/100 kcals
Choline 3,000 mg/kg 3,279 mg/kg 85 mg/100 kcals
Metabolizable Energy (ME) 4,125 kcal/kg (based on Atwater Calculation)
ME/cup 468 kcal/cup
Product Density 4.5 oz./cup
Digestibility 85.0 % 93 %
As Fed Digestibility (protein 84%, fat 95%, carbohydrates 91%)
PH Urine 7.0
and because my dogs do not appear to be lacking any nutrients, based on what i see daily and based on the resluts of their exams. if a problem/deficiency should appear/occur, i will adjust their diets accordinally.
and i guess i'm picky, due to working with animals, and after seeing all the dogs we are able to board in our kennels (150) sometimes on a daily basis) and the condition of some of them, yes, based on a high percentage of what they're being fed, after almost 4 years, i've seen enuff "questionable" looking dogs, both boarding and as a tech, to make me want to feed my dogs the best that i can afford.
but again, you have to do what works best for you. i'm just a food snob, i guess you could say, because SO many dogs cross my path on a daily basis.
anyhow, hope this helps you some. again, it's just MY .02....
i wish you the BESTof luck and
bon appetite!!!