In complete contrast to this, I went to Pets Corner (part of Wyevales) last week and asked for advice about getting Purdey to lose some weight, and the amount of information they knew about their products astounded me!
They explained that the reason that Luna seems to prefer Purdeys food (Bakers) is because it is full of sugar and fat and therefore tastes better but is bad for them.
I asked if JWB was a better bet, and she said it was better, but not as good as it used to be because they have reduced the % of protein in their products.
She pointed out 3 brands (Arden Grange, Symply and another I cant remember) that she said all had the best quality of ingredients - - She was even able to tell me where the meat was sourced from etc. I was so impressed, I'll be doing all my shopping there from now on.