AngularJS: contagem de itens filtrados

Estou mostrando subconjuntos de uma lista se uma caixa de seleção estiver marcada. Gostaria de substituir o X ao lado da caixa de seleção pela contagem da lista que corresponde aos critérios de seleção. Eu tenho um plunker que faz tudo, menos contar o subconjuntoaqui.

Meu controlador fica assim:

var app = angular.module('app', []);

app.controller('MainController', function($scope){
  $scope.cbMarvel = true;
  $scope.cbDCComics = true;

  $scope.heroes = [
    {
      id: 1,
      name: 'Iron Man',
      fname: 'Tony',
      lname: 'Stark',
      location: 'Stark Tower',
      comic: 'Marvel'
    },
    {
      id: 2,
      name: 'Batman',
      fname: 'Bruce',
      lname: 'Wayne',
      location: 'Bat Cave',
      comic: 'DC'
    },
    {
      id: 3,
      name: 'Superman',
      fname: 'Clark',
      lname: 'Kent',
      location: 'Metroplis',
      comic: 'DC'
    },
    {
      id: 1,
      name: 'Daredevil',
      fname: 'Jack',
      lname: 'Murdock',
      location: 'Court Room',
      comic: 'Marvel'
    },
    {
      id: 5,
      name: 'Flash',
      fname: 'Barry',
      lname: 'Allen',
      location: 'Speedline',
      comic: 'DC'
    },
    {
      id: 6,
      name: 'Hulk',
      fname: 'Bruce',
      lname: 'Banner',
      location: 'Labratory',
      comic: 'Marvel'
    },
    {
      id: 7,
      name: 'Hawkeye',
      fname: 'Clint',
      lname: 'Barton',
      location: 'Nest',
      comic: 'Marvel'
    },
    {
      id: 8,
      name: 'Thor',
      fname: 'Donald',
      lname: 'Blake',
      location: 'Asgard',
      comic: 'Marvel'
    }
  ];
});

E minha visão é assim:

<!DOCTYPE html>
<html ng-app="app">
  <head>
    <link data-require="bootstrap@*" data-semver="3.2.0" rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.2.0/css/bootstrap.css" />
    <link data-require="bootstrap-css@*" data-semver="3.2.0" rel="stylesheet" href="//maxcdn.bootstrapcdn.com/bootstrap/3.2.0/css/bootstrap.min.css" />
    <script data-require="bootstrap@*" data-semver="3.2.0" src="https://maxcdn.bootstrapcdn.com/bootstrap/3.2.0/js/bootstrap.js"></script>
    <script data-require="[email protected] current" data-semver="2.0.3" src="http://code.jquery.com/jquery-2.0.3.min.js"></script>
    <script data-require="[email protected]" data-semver="1.2.20" src="https://code.angularjs.org/1.2.20/angular.js"></script>
    <script data-require="angular-ui-bootstrap@*" data-semver="0.11.0" src="http://angular-ui.github.io/bootstrap/ui-bootstrap-tpls-0.11.0.min.js"></script>
    <link rel="stylesheet" href="style.css" />
    <script src="script.js"></script>
  </head>

  <body ng-controller="MainController">
     <fieldset>
        <legend>Comments Log</legend>
        <div class="row">
            <div class="col-md-4">
                <input type="checkbox" ng-model="cbMarvel"/> Marvel [X]
            </div>
            <div class="col-md-4">&nbsp;</div>
            <div class="col-md-4">
                <input type="checkbox" ng-model="cbDCComics"/> DC Comics [X]
            </div>
        </div>

        <div class="row">&nbsp;</div>

        <div class="row col-md-10">
            <div ng-if="heroes.length == 0"><b>No Heroes Found!</b>
            </div>
            <div ng-repeat="h in heroes | filter:{comic:'Marvel'}" ng-show="cbMarvel">
                {{ h.name}} - {{h.comic}}
            </div>
            <div ng-repeat="h in heroes | filter:{comic:'DC'}" ng-show="cbDCComics">
              {{ h.name}} - {{h.comic}}
            </div>
        </div>
    </fieldset>
  </body>

</html>

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