Please say it “Zed,” which rhymes with “bed.” Now that you’ve got that down, here’s the formula: extremely compact rooms, but lots of room under the duvets; glassy sleek style; and a lobby that’s always abuzz with breakfast, coffee, or free daily wine. The formula works because there are design smarts where they count: Shower nozzles swivel the way you need them to, towels are plump and copious, you can control your thermostat. They poured cash into the bedding and the 40-inch TVs but did without closets and drawers. Very cheap rooms may not have windows. Note that if you share a room with a platonic friend, bathrooms are enclosed only by panels of fogged glass. If you try to book too far ahead, they have a nasty trick of charging you £300 for a room. My favorite locations, for convenience: Soho and Piccadilly.