The Petronas Towers building may be taller than the KL Tower, but the observation deck at KL Tower is at a higher elevation, and still worth going to for a birds eye view of the sprawling city of Kuala Lumpur.
We purchased tickets for the observation deck, the sky deck and entry to the skybox was included in our admission ticket. The view from either the observation deck or sky deck was great, and in my mind, the views weren't as 'frightening" as the Burj Khalifa in Dubai!
As much as the skybox platform looked a tad scary, we were hoping to try it out. However, entry to the skybox is by your admission ticket number, and you have to wait until your admission ticket number is displayed on the electronic board at the skybox. Given our admission ticket number, we were going to be in for a very long wait, and decided not to wait.
Recommend purchasing admission tickets online, or arrive as soon as the KL Tower opens to purchase your tickets at the self-help vending machines (there didn't appear to be a ticket sales office to purchase your tickets from!). There are customer service people there to assist you with your purchase at the vending machines if you need assistance.
We caught a taxi from our hotel to the KL Tower, assuming we wouldn’t have any issues catching a return cab. Unfortunately, there isn’t a dedicated taxi rank at the KL Tower, and trying to call a cab from our mobile was impossible, even though we had global roaming services available to us. Recommend pre-arranging a cab or other means of transport for your return journey from KL Tower.