Just thought I'd add that alot of dog food lacks taurine which is essential to the well being of cats - both for their heart and their eyesight.

The same can be said for dogs but the difference is that dog's bodies are able to manufacturer taurine where as cats must get taurine entirely from what they eat as they aren't able to produce it. Therefore complete cat foods are formulated to include enough where as dog foods aren't likely to contain enough.

I know you have already taken others advice but thought I'd add this as another reason!