Thank you very much all of you.. I really appreciate you guys for putting out such a great discussion. I have used the script by muthukumaran and studied the results. The results were convincing.

Actually, I am referring to two different databases on the same instance here. Both of them are mission critical and at the same time, Application team has agreed for a weekly outage of two hours on both the databases. So, we can do the rebuild offline.

Now, I have a small concern here... While executing the stored procedure on one of my databases on a test server.. I have noticed CPU usage was maxed out. usually, this box sits at 45-50% CPU usage.. Also when this SP was running, I had none other than me logged into this machine... any comments on its effect on my prod server...