The Checkpoint itself is not the actual attraction (unless you are fond of fake Soviet soldiers) - however the municipality has been so kind as to erect a large and comprehensive overview of the Cold War history along the construction sites of Friedrichstraße right next to it.
If you want to refresh your memory or learn all about the Berlin blockade, which sector was allocated to which of the allies and how people tried to escape from East Berlin, this is actually a place worthwhile going to in order to grab some outdoor history lessons for free.
Walking to the Checkpoint from Friedrichstraße (S&U-Bahn) takes some 15 minutes and is a lovely stroll down one of the main shopping streets...