I have eaten lunch and dinner at Sci Fi. Burgers are not on the menu at dinner, so if your family wants that you should stick with lunch. At dinner, I had the fried catfish dinner and it was pretty tasteless, but okay. DH had the shrimp pasta and it was YUMMY, with lots of shrimp.
I think this place does it's best work at lunch with the burgers and shakes, really. The atmosphere is great, probably the best in WDW, and is a great escape on a busy day.