Must visit. Buy tickets in advance and have it you...

Must visit. Buy tickets in advance and have it you phone, download it to pdf so you can zoom it and the staff can properly scan it. Take the time to enjoy the view in all possible angles. Restrooms and coffeeshop is available in the tower.

Personally I think that due to the time that takes making good pictures from outside of the tower, then ascending in the elevator to the 2 leves available, and finally get to the top it may take you at least minimum 3 hours at least. Don't rush it worth the visit and your time.