We have eaten there twice and went back the second time just for the food! It's very good, everything we've tried, and the portions are huge so easily split between two adults, which makes it a very affordable meal!
Depending upon waiter, you can have a very interactive exp there. Our second visit, we were very very tired and our waitress picked up on that quickly and just played with us a little bit.
The atmosphere is very fun, lots to look at, and interaction with other tables.
Sci Fi is also fun, and usually a hit with kids, since they sit in "cars" and watch a drive in movie. It's very dark in there, and not set up for conversation, but a nice break from the usual. Lunch is better, their burgers are the best thing they have. It's the best themed restaurant at WDW, IMO.