• We define the comparison criteria before looking at any product, and publish them in the guide.
  • Every figure is sourced from the maker's own disclosures or an official regulator or statistical release, and linked.
  • Products are ranked only after testing against the documented protocol on our testing process page.
  • Commercial relationships are disclosed on the page and never change the ordering, inclusion or assessment of a product.
  • Guides carry a last-reviewed date, and we withdraw a guide rather than let it go stale.