<label>
    <input
        type="radio"
        ng-model="ngModel"
        name="addthis-{{toolPco}}-enable"
        ng-value="true"
        ng-selected="{{isEnabled()}}"
    />
    Enabled
</label>
<label>
    <input
        type="radio"
        ng-model="ngModel"
        name="addthis-{{toolPco}}-enable"
        ng-value="false"
        ng-selected="{{!isEnabled()}}"
    />
    Disabled
</label>