Whether you're a dipper, a drizzler, or simply a salt-and-pepper purist, none of that counts for anything if your chips aren't up to scratch. Crispy on the outside , fluffy in the middle – that's the only benchmark for proper chips. Whilst household names like McCain Foods rule the freezer section, they come with quite a hefty price tag. Fortunately, supermarket own-label options are improving dramatically. To discover whether splashing out extra cash is genuinely worthwhile, I sampled four