Maybe it\'s a rookie mistake, but I can\'t seem to access the $scope.model\'s $ngModelController so I can grab the $viewValue from it.
I like the directive alternative. Essentially the ui-mask directive isn't doing what you want, so you might as well write your own directive.
You shouldn't have to pass inicio to your view-value directive. Instead, add your own parser to ngModelCtrl.$parsers. Here's an example: https://stackoverflow.com/a/15556249/215945