Ilike real flight better because you can select an option to keep the horizon in view (at least most of the time) which makes it much more realistic for me. FMS is hard to use for me some times because you loose orientation quite often (perhaps I have to zoom out or something). Both will teach you how to fly a plane comming towards you or to the side though. Thats not gonna change. The models in realflight are a lot better though.

P.S. I have the Nitromodels E-Sky Simulator and would highly suggest it. It's very affordable at 20 dollars and for me, I think shipping cost more then it does some how (how in the hell is nitromodels making money off this item???)... In anycase, its saved me a lot of time, money, and fustration. If you can't afford 20 bucks, you can't afford to fly as this will really save your friend a lot of money and at least you get to get your realflight/controller back in the end