I have eaten at both, but after my last experience in 2011 at Sci-Fi, I will never go back.
While waiting to be called up for our ADR (thank goodness my husband and kids were not waiting with me), I was sitting enjoying a quiet moment to myself on the bench beside the podium just inside the doorway. I happened to glance down at my shoe, and to my utter horror, saw the largest cockroach I have ever seen crawling out from under the bench! As I jumped up and away, it quickly scurried down toward the hall to the restaurant. A brave CM then ran over to the bug and tried to squash it with his foot. The roach was about half the size of his foot, so he had to stomp on it about a dozen times. Poor bug, poor CM, poor me who spent the rest of my time at Sci-Fi with my feet up in the car, squinting in the dark to check the inside of my turkey sandwich. My family had a great time, and they can't understand why I don't want to go back.
Yes it's Florida, there are bugs and snakes and swamps, but I will never, ever, go back to Sci-Fi.
BTW the food at 50's is great, so I will be going back there!