I got FS 2004 for christmas, eye candy is great but it just doesnt really compare to flying. I started flying in january and havent really flown FS2004 since becasue its just not like flying. Maybe its because of my joystick (Saitek X36combo). It doesnt feel like flying at all, you really need something with some feedback. I dont know whether I would spend 70 odd euro or so on it. It would probably be better spent on real flying although that said it does give you basics of Instrument Flying.
Steve