I had the chance to enter in this amazing building, but, unless you are over 60's or other lift requirements, you need to do the stairs not many, just bring some cold water with you and remove your jacket it will get hot.
By the way you can take a picture if you a brave enough on the glass who facing the road underneath, about 53 meters height .. Scary Not easy to believe there is glass there.
Don't try to get there where the weather is rainy, it's useless for pictures, unless you like it.
Enjoy