The cheap varieties are cheap because they are full of wheat and maize. Some of the working formulations are decent quality but you're up to £30 a bag then which is comparable to lots of other brands. CP30 has a decent meat content but I won't feed anything with corn in it and certainly not wheat.
I feed CP Xtra, my dog (retired Greyhound) does great on it, lovely shiny coat and excellent muscle tone. It's what I was recommended by the rescue when we got him and when they saw him 6 months later they were really impressed at his condition
Sorry, yes, I should have pointed out that I'm coming from a working dog POV! It's no coincidence that their working formulations aimed at sled dogs are all wheat-free, sibes and mals are notorious for their inability to cope with high grain diets and I know so many that can't handle wheat (including one of my own).
To be fair any of their varieties are better than supermarket offerings and a few are comparable to the well known branded foods at a much better price so can't argue there. I just dislike their cheaper offerings, too much grain IMO.