AngluarJS Checkbox becoming unchecked

I have a scenario where I load the page with a check box already checked. In the load of the controller I make a call to a web api to load the content of the web api call into a table.

The problem is, after the web api call happens, I loose the fact that my check box is checked. I am not sure what the problem is. I created a small example of it in a plunk, and it happens there.

Plunker: http://ift.tt/2esq45L

      var Url = "http://ift.tt/2ePuRMG";
  self.$http.get(Url, this.requestConfig).success(function(data, status, headers, config) {
    console.log('success', data);
  }).error(function(data, status, headers, config) {
    // log error
    console.log('error', data);
  });

What should happen is the check box remain checked after the http get happens.

I am using the controller as syntax, and am wondering if I am missing something in this scenario...