Buy a ticket before coming here...the lines are LONG and if you need to purchase the ticket there it will only delay how fast the line moves.
I visited this exhibit Saturday around 7:00pm. There were two really long lines that took about 20 minutes. There were people complaining, especially those who have problems with their knees. There was an elderly couple I felt really bad for because they had to wait in the line and I did not see a section for letting them go faster.
Overall, the lights are really neat and I had a great time walking around. It takes about an hour to see everything. Even though there were some shows going on, they were tucked away in a corner and it was hard to get to. There was also very limited seating available which meant that a lot of people were standing and obstructing the view.
I am glad I had the chance to see this but I wouldn't go back unless I had kids.