How rewarding is S&T, Research ??

My primary goal is currently to break into BB's Markets divisions . I think it suits me better that corporate finance and more.. Also, I like the idea to work during the time the financial markets are open (i.e. not work at weekends).

But I wonder; How rewarding is sales & trading these days, actually? I mean it's not like you'll earn a 100 000 £ the first year right? Or as in the movies, getting rich by the end of the first month.....

Say that you begin as an intern, you get an offer after you graduate... you pass the first year, continuing a second year, and you'll continue a few years more... What should I then expect to earn during these years?? (as a sales person, trader, researcher or other)

I ask this, not only because I want to earn a lots of money... but simply because I want to compare the rewards of a career within S&T to the time i put in the studies and extra curricular stuff that I do and the opportunity cost that I pay while studying for 5 years..

There are a lot of speculations among my classmates but I would love to hear from someone with experience :)

Thank's in advance!