The best thing about the Shake Shack inside the Fulton Center mall is the location: It’s on the top floor, which is a curved catwalk, so you feel as if you’re suspended in mid-air. There’s a fair amount of seating, almost all of which has a view, either out to the street or, even better, down into the subway station. (Try to ignore the horrid pink glow that comes up now and again from the video screens.) The worst thing about the restaurant might also be the location. The entrance is extremely narrow, as is the adjacent pick-up area. The line gets corralled out the restaurant, down the spiral staircase, and along the floor below. As for the menu, it’s the same, with the exception of three new concretes. Note: This Shake Shack is open from 7 a.m. on weekdays.