My personal tip how I check the suitability of my cat food.
1) Eat and taste the cat food yourself
If you like it, your cat probably will too but if salty, you can snack on it while watching movie and dont share it with your cats.
2) Soak a kibble in a glass of water. Does the kibble and the water change color? If yes, coloring may have been added.
3) Take out the soaked kibble and mash it with your finger. Does it feel like your facial scrup? If yes, the kibble is filled with grain. If the mash kibble felt sticky, then it filled with gluten.
4) You had examine what goes in, now examine what come out
5) Drop some poo into clean toilet bowl. Dont flush. After a while, is there any coloring discharged from the poo?
6) Does the poo floating? Indigested hairball and grain sometime made the poo lighter and float.
7) Wanna mash your cat poo with your finger to find out if it got the sandy feel? Probably not
then dont! Kibble filled with grain will cause the poo to be soft and smelly.
8) Feed you cat with boil chicken (no salt added) and compare the quantity and the odor of the poo. Probably with chicken, you get longer gap for repeat business with less amount, less smell.
9) Raw meat diet is superb but make sure you get your vet advise on deworming frequency as worm tend to thrive in raw meat. Still need to monitor poo for worms. Tapeworm are resilience to normal deworming liquid.
10) Cats are individual. No 2 cat are the same. One food may be good to one cat but may not to others.
The above tips applies to my 8 cats with no reservation. Apply at own risk.