Hi!
So I'm not studying at Sciences Po my but I live in Paris and I have many friends there (in Journalism, History, Geography and Political Studies that is, so my input might not be as valuable as you'd hope). All I know is that the 'Sciences Po' isn't everything : for example the journalism department is not really recognised by employers, contrary to much cheaper and more selective programmes. There's also a rather shared belief around here that it's easier for international students to get in because Sciences Po sees them as cash machines. However, I heard the same thing about the University of Edinburgh and it doesn't mean that it's true or that international students don't get extremely valuable degrees there.
Anywho, what I'm saying is that you should look into the specific programme you're after carefully, in terms of reputation, sure, but also in terms of content. Also, since money is an important factor, don't forget that Paris is quite expensive. What makes it cheaper than, say, London for students is usually low tuition fees, which clearly is not the case for your specific programme.
I'm sorry that's everything I can tell you, I hope it helps a little.