Is attending a more expensive and prestigious foreign university a good financial investment? Here's the question: is university a sound investment? I'll be clear, since I know that this situation and this questions are experienced by many people. I'm going to face very soon the choice of where to go attending my Msc courses and obviously, after having decided which universities suit my tendencies better, financial considerations come on the way. I don't want to hear considerations like "yeah,it's all about your dreams, if you really want to go there then it's a worthy investment" because let's face it, even with your dream job life with 1000£ a month isn't easy. I'm not even complaining about how this world can be elitarist due to the high fees and life costs, I'm just pondering the best opportunities.
The choice is between staying here in my country where costs are way lower or trying for the upgrade in the best (and expensive) foreign university (namely I'm now considering Oxford, Cambridge, Imperial and Eth). I was wondering then if the 20000\50000£ investment is justified by a better salary and effective enhanced working chances? And in case of the decision to pursue an academic career, is it amortised in a reasonable amount of time?

Has someone experienced this path or similar one and can tell me something about it?

Just to give some feedback: I'm from one of the good italian universities and with grades making possible a decent (hopefully) prospect of career even here, either in or outside the academic world.

EDIT since it might be useful, I'm studying mathematics and planning to have my master in applied mathematics. The options are to get a specialization in financial mathematics or a general applied mathematics Msc that could yield to further academic continuance or to job in industry.
Ok, I have answer to this as I did finish all my higher education in the UK, and still living/working here.

Money Buys you a Place But Not a Future: Yes, you can spend money and get to very decent universities; but: 

Exceptions: The Oxford, Cambridge, and Edinburgh are very wealthy and well known and funded, so they don't care much about anyone's money to be honest; however this might differ based on your field. But, the general rule, don't count on getting a place over there by flashing money.

University: Not so many universities currently looking for hire from postdoc level, yet alone PhD level. There is a mayhem over this, just talk to an academic living in the UK. 

Conclusion Back to your question, no by paying extraordinary amount of money you will not get a better financial future compare to finishing your studies within Italy.