Sandwich prices are 5p-10p dearer than in standard M&S food halls, because there are no self-service tills, only manned ones, so all is harmonious. This is the smaller of the two M&S branches in Liverpool Street station(things might be different in the upper floor branch). M&S should scrap all their self-service tills, even if it means prices rise slightly. They are stressful for customers to use and cause staff in other branches to be rude and bad-tempered. In this shop, polite, smiling staff deal promptly with your purchase — even suggesting additional items you might like to buy. And the queue, though sometimes long, goes down really quickly as at least 5 tills are always open.