I found some good cons here:
The noscript element only detects whether the browser has JavaScript enabled or not. If JavaScript is disabled in the Firewall
I create a full height, full width, position:fixed div in all pages with some id .
enable JS buddy
$('#noscript_div').hide();
$(document).ready(function(event){
});
I am not an expert . This worked for me . I am sorry but, this case will suit only if you want the user to have his javascript enabled always