Dynamic Magento controller Actions with PHP __call() method. Works without any rewrite condition. Good or bad? ;-)

gistIdController.php

<?php
class XXX_FileRestriction_IdController extends Mage_Core_Controller_Front_Action
{

    /**
     * Allow URLs like http://domain.tld/downloader/id/4711
     * without any rewrite syntax
     *
     * @param string $method
     * @param array  $args
     *
     * @return bool
     * @throws Varien_Exception
     */
    public function __call($method, $args)
    {
        switch (substr($method, -6)) {
            case 'Action' :
                $id = (int)str_replace('Action', '', $method);
                $this->_downloader($id);
                return TRUE;
        }
        throw new Varien_Exception("Invalid method " . get_class($this) . "::" . $method . "(" . print_r($args, 1) . ")");
    }

    /**
     * @param $id
     *
     * @return bool
     */
    protected function _downloader($id)
    {

        $isLoggedIn      = Mage::helper('customer')->isLoggedIn();
        $customer        = Mage::helper('customer')->getCustomer();
        $customerGroupId = (int)$customer->getGroupId();
        $customerId      = (int)$customer->getEntityId();

        /**
         * @var $collection XXX_FileRestriction_Model_Resource_Files_Collection
         */
        $collection = Mage::getModel('xxx_filerestriction/files')->getCollection();
        $collection->addRestrictedIdsFilter(array($id));

        if ($collection->count() == 0) {
            return $this->_sendError404();
        }

        /**
         * @var $file XXX_FileRestriction_Model_Files
         */
        $file = $collection->getFirstItem();

        $allowGroups = $file->getAllowCustomerGroups();
        /*trimExplode in short*/
        $allowIds = array_flip(array_merge(array_diff(array_map('trim', explode(',', $file->getAllowCustomerIds())), array(''))));

        $isDownloadAllowed = FALSE;
        if (!empty($allowGroups) || !empty($allowIds)) {
            $isGroupAllowed      = ($allowGroups & pow(2, $customerGroupId)) > 0;
            $isCustomerIdAllowed = isset($allowIds[$customerId]);

            if ($isLoggedIn && ($isGroupAllowed || $isCustomerIdAllowed)) {
                $isDownloadAllowed = TRUE;
            }
        } else {
            $isDownloadAllowed = TRUE;
        }

        if ($isDownloadAllowed) {

            $downloads = (int)$file->getDownloads();
            $file->setDownloads($downloads + 1);
            $file->save();

            if (Mage::helper('xxx_filerestriction')->isExternalUri($file->getFileUri())) {
                $this->_redirectUrl($file->getFileUri());
            } else {

                $filePath = Mage::getBaseDir('media') . DS . $file->getFileUri();
                $fileName = basename($filePath);

                $content = array(
                    'type'  => 'filename',
                    'value' => $filePath,
                );

                $this->_prepareDownloadResponse($fileName, $content);
                return;
            }

        } else {
            return $this->_sendError404();
        }

    }

    /**
     * @return bool
     */
    protected function _sendError404()
    {
        $this->getResponse()->setHeader('HTTP/1.1', '404 Not Found');
        $this->getResponse()->setHeader('Status', '404 File not found');
//        $this->getResponse()->setBody('404 File not found');
        $this->_prepareDownloadResponse('notFound.txt', 'File not found'); /*???*/
        return;

    }

}