The lining of Purina has been tested by all and it is always a bit rausgefuttert from the bowl, but not nearly as much as the standard feed. The skin of my cat has always been beautiful and has so far not changed. I can not say anything about the hairballs because all cats are outdoor cats in the house and I have very rarely the hairballs.
The smell of food is for my nose okay and for the cats probably because otherwise they would not eat the food. The high cereal content does not interfere with my cats too, because they have trouble balancing by mice and they have, because I find often enough still remains part :-(
All in all okay. As additional food I can make it, as a standard feed will however not make the grade.