Let me say, first off, that I have no idea what the food is like in this place. I think it´s probably quite ok, in a cafeteria style ham and egg sandwich way.
Not that it matters. The view´s the thing. If you can get one of the tables by the windows, you won´t care much if it´s ashes and soap on your plate.
Madrid isn´t one of your famously picture pretty cities. I think that´s mostly because it´s hard to get a clean view. You´re always on the ground, looking up at buildings that are too close. Of course, you can cross the so-called river and get a fine view of the Palace, and there´s las Vistillas, and the stunning mirador de Moncloa. But you have to go out of your way for them.
This is right in the hub of the action.
Next time you´re on Gran Vía being jostled to death while you queue for cinema tickets, or wait for a cab, wheighed down by your shopping, remember me. Stop complaining about the noise, the traffic and the fumes, and go up to the cafetería in the Corte Inglés de Callao.
You´ll have a clear view of the whole southern skyline, a roof over your head, and coffee. It will make you appreciate the beauties of Madrid.
I think so , anyway.