Roland System 100m

hello,
seem to be a new member
hope ya don't mind too much:)
I have some questions, I am a great fan of Hans Zimmer (filmmusic 
composer) don't know if it rings any bells out there, but I found 
out he uses the Roland System 100m. Now I am beginning my studies at 
the conservatory this year in Belgium. And  wanted to keep my hands 
busy (besides playing classical piano) with the electronic music. My 
knowledge about synths and creating orchestral scores is minor. What 
can you tell me about a Yamaha CS 80 with midi. What are advantages 
of midi? And how will electronic sounds sound very realistic. What 
about Roland JD 800 and 990?
I know these are a lot of questions, but I hope someone out there 
can help me out. I don't know a lot of people in Belgium that are 
interested in these things, so I figure I should try the internet.
Anyways, I would sincerely appreciate your help!
Thank you for your attention,
greetz
de_masse