In express 4.0 they got it right :)
res.sendStatus(statusCode)
// Sets the response HTTP status code to statusCode and send its string representation as the response body.
res.sendStatus(200); // equivalent to res.status(200).send('OK')
res.sendStatus(403); // equivalent to res.status(403).send('Forbidden')
res.sendStatus(404); // equivalent to res.status(404).send('Not Found')
res.sendStatus(500); // equivalent to res.status(500).send('Internal Server Error')
//If an unsupported status code is specified, the HTTP status is still set to statusCode and the string version of the code is sent as the response body.
res.sendStatus(2000); // equivalent to res.status(2000).send('2000')