I love Sci Fi too. Its the one and only place we have been to each of our 10 trips, we just think its a hoot and have never had anything but a great meal with great service. Its also very relaxing in there, and quiet! Everyone is watching the movies so you don't have quite the usual din you have at most WDW restaurants.
I also enjoy Prime Time but if you have members of your party that don't enjoy hamming it up with servers it might not be the right choice. We love that but I know one night these two ladies were clearly horrified when their server started scolding them for not eating their food. I felt sorry for them and the server, I think he was embarrassed as soon as he realized they weren't in the mood for his antics!