We visited on a warm and sunny Monday morning (around 10am) so did not have to wait too long to get up to the top (about 20 minutes after bag checks, ticketing etc). We had purchased our tickets online in advance here in the UK - if you do the same, make sure that you check with the front desk first in advance as sometimes you only print out a 'voucher' that you will need to exchange for a proper ticket before entering the queue. We did not realise this and were only told once we got to the front of the queue. However, they let us back through the gift shop to get that sorted and we did not have to queue again, luckily. The process to get people up was well organised.
Once up the top, the views were amazing on every side. It was a clear day so we could see for miles and miles. We did not do the 'Tilt', although there was no wait for it. I wish there was somewhere to go outside to view but this is only an indoor attraction.
The cost was about £32 for us both and it was worth it. I would definitely recommend visiting here if you have the time and the weather is good.