If you happen to be near this building then it's worth going to see it, and you may even get to see the President arriving or leaving. There is also a changing of the guards which if you time it right you may get to see. It's near to many other attractions in Warsaw, so you may pass it unintentionally as I did. There are apparently often protests and demonstrations taking place outside here, but there didn't seem to be any on the days I went past.