Hey Bharat,
None of us really know with exact certainty as that is for CIC to know. Also, technically, they can deny your application at any stage. They can even deny issuing you a Visa after requesting the passport, and they can deny you entry into Canada when you attempt to "land" after receiving the immigrant visa. Now, with that disclaimer out of the way, let me say that based on anecdotal evidence, you can be fairly certain that they are pretty much done with approving your application once they request RPRF from you. Of course, it is possible that the VO or the intern working on your application may have requested RPRF before other areas on the application have been assessed and passed and if that is the case then they may require additional information but such a scenario is highly unlikely.
So in Summary, what I would say is that you should definitely feel more relaxed now than you did BEFORE you received the RFPRF but you will only be done with all of this when you have landed