Even though the visibility was at 50 when we went up it is spectacular! We failed to print our vouchers from Viator and the staff at Top of the Rock could not have been more helpful. We emailed the confirmation to them and they printed them for us. We went about 4:30 just as the sun began to go down and saw the lights coming on all over the city.
Definitely do this!
Really good. Voucher worked well and we were able to visit at a time convenient to us without a queue.
With coupon from Viator, visiting Top of The Rock was a breeze. I recommend going up the Rock at sunset to see the spectacular view. Wait til the city dazzles as it becommes all lit up! wonderful!