I finally got on it last night and was able go twice. The sign said 50 minutes the first time, waited just under 30 minutes. The second time it said 30 minutes and waited about 15 minutes.
The ride at night was very enjoyable. The fans in the queue made the wait nice and the ride experience was exceptional. We felt like the ride was too short, but the combined 45 minutes of waiting for two rides made it worth the fun when you combine the length of the ride. Really, I would have loved for this be like twice the length (understand why that's not feasible), but for what it is, it's a great attraction.
BTW, the park was empty last night. 15 minutes for TSMM, 5 minutes for Alien Swirling Saucers. It was wonderful.