It will depend on how long the standby line is, and during Christmas week, it will likely be long. We rode it in October which is moderately busy. It took us roughly 15 minutes to get from entering the FP queue to entering the first pre-show room. Between the two pre-show rooms, probably another 15 minutes. So by the time we were done, about 30-40 minutes in total. But like PPs have mentioned, you're not standing in a queue during that time. The pre-shows break that up.
And honestly, even if it is 51 minutes, its worth it if you haven't ridden it yet.