We purchased a combo ticket with the hop on hop off bus and with the pre-purchased tickets were able to skip the queue line.
The views from the tower were great.
we had a snack at the cafe and that was good also ( you need to order at the register and it will be brought to the table- we sat for a while waiting for a server and it doesnt work that way)
The Skydeck requires a 2nd elevator and the views are not that much better than those on the main observation deck.




