Is Wiltshire in England? I have no idea what types of kibble they sell across the pond, but just look for kibbles without:

- Artificial coloring
- Artificial flavoring
- BHT, BHA, ethoxyquin, propylene glycol
- Any type of grain in the first three ingredients (your first three should be meat)
- No vagueness, like "Animal Meal" or "Meat meal". You want specific sources like "Chicken", "Turkey Meal", "Venison", etc.
- No by-products

If the kibble you have in mind doesn't contain any of the above, chances are it's a pretty good kibble. Hope that helps you narrow it down some