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"Our supermarket survey asked 11,492 Which? members in October 2012 about the supermarkets they've shopped at over the last six months. Each was rated for customer service, filling your trolley, fresh produce quality, pricing and store environment. The filling your trolley rating covered product range, how easy it is to find items and how likely they are to be in stock. While the pricing rating covers value for money and special offers. The overall customer score is a combination of customer satisfaction and the likelihood theyd recommend it to a friend."