I made a property editor that is a text field that can only be edited by users belonging to the user types you select in the data type configuration screen (everybody else gets a read only version). Would be very easy to modify to make it work with a checkbox instead. Here's the code for each file.

UserTypeApiController.cs

namespace MyProject.App.Controllers
{

    // Namespaces.
    using System.Linq;
    using System.Web.Http;
    using Umbraco.Web.Mvc;
    using Umbraco.Web.WebApi;

    /// <summary>
    /// Controller for Umbraco user types.
    /// </summary>
    [PluginController("Rhythm")]
    public class UserTypeApiController : UmbracoAuthorizedApiController
    {

        #region Action Methods

        /// <summary>
        /// Returns the ID of the current user's user type.
        /// </summary>
        /// <returns>
        /// The CSV path.
        /// </returns>
        /// <remarks>
        /// The URL is "/umbraco/backoffice/Rhythm/UserTypeApi/CurrentUserTypeId".
        /// </remarks>
        [HttpGet]
        public int CurrentUserTypeId()
        {
            return this.UmbracoContext.Security.CurrentUser.UserType.Id;
        }

        /// <summary>
        /// Returns all user types in Umbraco.
        /// </summary>
        /// <returns>
        /// The user types (an array of objects, each containing an ID and name).
        /// </returns>
        /// <remarks>
        /// The URL is "/umbraco/backoffice/Rhythm/UserTypeApi/GetUserTypes".
        /// </remarks>
        [HttpGet]
        public object GetUserTypes()
        {
            return this.Services.UserService.GetAllUserTypes()
                .OrderBy(x => x.Name).Select(x => new
                {
                    id = x.Id,
                    name = x.Name
                }).ToArray();
        }

        #endregion

    }

}

App_Plugins/ProtectedText/user-type-picker/user-type-picker.html

<user-type-picker model="model"></user-type-picker>

App_Plugins/ProtectedText/user-type-picker/user-type-picker.js

(function () {

    /**
     * The controller for the user type picker directive.
     */
    function Controller($scope, $http) {
        this.injected = {
            $scope: $scope,
            $http: $http
        };
        this.getUserTypes();
        $scope.isSelected = this.isSelected.bind(this);
    }

    /**
     * Gets all of the user types and stores them on the scope.
     */
    Controller.prototype.getUserTypes = function () {
        var url = "/umbraco/backoffice/Rhythm/UserTypeApi/GetUserTypes";
        var $scope = this.injected.$scope;
        var $http = this.injected.$http;
        $http.get(url).success(function (data) {
            $scope.userTypes = data.map(function (item) {
                return {
                    id: item.id.toString(),
                    name: item.name
                };
            });
        });
    };

    /**
     * Indicates whether or not the specified option is selected.
     * @param userType The user type to check for selection against.
     */
    Controller.prototype.isSelected = function (userType) {
        var $scope = this.injected.$scope;
        var items = $scope.model.value;
        if (items && items.length) {
            for (var i = 0; i < items.length; i++) {
                if (items[i] === userType.id) {
                    return true;
                }
            }
        }
        return false;
    };

    /**
     * A directive that allows user types to be picked.
     * @returns {{restrict: string, templateUrl: string, controller: Controller, scope: {model: string}}}
     */
    function directive() {
        return {
            restrict: "E",
            templateUrl: "/App_Plugins/ProtectedText/user-type-picker/user-type-picker-directive.html",
            controller: Controller,
            scope: {
                model: "="
            }
        };
    }

    // Register directive.
    angular.module("umbraco").directive("userTypePicker", directive);

})();

App_Plugins/ProtectedText/user-type-picker/user-type-picker-directive.html

<select multiple size="20" ng-model="model.value">
    <option ng-repeat="type in userTypes" value="{{type.id}}" ng-selected="isSelected(type)">{{type.name}}</option>
</select>

App_Plugins/ProtectedText/package.manifest

{
  "propertyEditors": [{
    "alias": "Rhythm.ProtectedText",
    "name": "Protected Text",
    "icon": "icon-code",
    "group": "Text",
    "editor": {
      "view": "~/App_Plugins/ProtectedText/protected-text.html",
      "valueType": "TEXT"
    },
    "prevalues": {
      "fields": [
        {
          "label": "User Types",
          "description": "These are the user types who will be allowed to edit the field data.",
          "key": "userTypes",
          "view": "~/App_Plugins/ProtectedText/user-type-picker/user-type-picker.html"
        },
        {
          "label": "Multiline?",
          "description": "Use a multiline text area rather than a single line text field.",
          "key": "multiline",
          "view": "boolean"
        }
      ]
    }
  }],
  "javascript": [
    "~/App_Plugins/ProtectedText/protected-text.js",
    "~/App_Plugins/ProtectedText/user-type-picker/user-type-picker.js"
  ]
}

App_Plugins/ProtectedText/protected-text.html

<protected-text model="model"></protected-text>

App_Plugins/ProtectedText/protected-text-directive.html

<div>
    <input ng-if="model.config.multiline === '0'" ng-readonly="readonly" type="text" ng-model="model.value" class="umb-editor umb-textstring" />
    <textarea ng-if="model.config.multiline === '1'" ng-readonly="readonly" type="text" ng-model="model.value" class="umb-editor umb-textarea" rows="10"></textarea>
</div>

App_Plugins/ProtectedText/protected-text.js

(function () {

    /**
     * The controller for the protected text directive.
     */
    function Controller($scope, $http) {
        this.injected = {
            $scope: $scope,
            $http: $http
        };
        $scope.readonly = true;
        this.checkPermission();
    }

    /**
     * Enables or disables the text field based on whether or not the current user has permission
     * to edit the field.
     */
    Controller.prototype.checkPermission = function () {
        var url = "/umbraco/backoffice/Rhythm/UserTypeApi/CurrentUserTypeId";
        var $scope = this.injected.$scope;
        var $http = this.injected.$http;
        $http.get(url).success(function (data) {
            var currentUserId = JSON.parse(data).toString();
            var items = $scope.model.config.userTypes || [];
            for (var i = 0; i < items.length; i++) {
                if (currentUserId === items[i]) {
                    $scope.readonly = false;
                    return;
                }
            }
            $scope.readonly = true;
        });
    };

    /**
     * The directive that facilitates protecting text fields so only some user types can edit them.
     * @returns {{restrict: string, templateUrl: string, controller: Controller, scope: {model: string}}}
     */
    function directive() {
        return {
            restrict: "E",
            templateUrl: "/App_Plugins/ProtectedText/protected-text-directive.html",
            controller: Controller,
            scope: {
                model: "="
            }
        };
    }

    // Register directive.
    angular.module("umbraco").directive("protectedText", directive);

})();

Nicholas, Thank you for the Input, At first I was just looking for a way to validate the user for just the enable checkbox, the I looked at the who process of where I was storing the two other values I needed for my postback method. So now I am heading down the direction you suggested and I am going to change the datatype to have a true/false and two text boxes, one for the end point url and the other for the data string to pass.

is working on a reply...