I understand that a lot of dogs have done okay on the cheaper foods.  Years ago my dad and I raised and trained stock dogs.  There were very few choices of kibble. Dog nutrition has come a long way in the last 15 years.  The only reason for Red Dye 40 is to make those cute, pretty pieces for us the human buyer.   Most of the lesser foods also spray on a flavoring.  In the industry it is ref. to as "kitty crack".  Sort of like the surgary cereals marketed to kids. 
At the end of the day you (collective you) will spend less because you will be able to feed less.  Higher nutrition value means the animal absorbs more.  Less poop means the dog/cat is absorbing more.  Cat litter boxes smell better, etc.

If you decide to try another food email the company.  Tell them you would like to try their food but the price differance makes it difficult.  Most will send you coupons.  With the exception of Diamond.  They just don't do coupons.  Fromm runs coupons on their face book page monthly.  Call Canidae and they will send you coupons.   

The insanely high rate of Cancer in dogs is frightening.  And approx. 30% of small dogs die of heart disease.  CSU is studying both of these issues now and hopefully will have a break through soon.

karen