Went on a fairly cloudy/snowy day and once we were above the clouds the views were amazing and even moreso once we got to the Cosmic Ray Station (don't expect to see anything amazing about the station but it is interesting as well.
Bring a marker along so you can put your name or something small on the station itself. Don't know if it is wrong or not, but we felt left out after seeing the hundreds of others who had written on it.
Dress for the weather. We did and it made a huge difference. Its off and on windy and if you are cold, its no fun. With the reward of the better views and to be able to say you were there, its worth it. There were a few people that did the walk in shoes and just a jacket with hands in pockets and a touque, but they didn't have as much fun as we did.
There was hardly any other tourists there so it made it alot better and you could take your time without being bothered.
The Starbucks in there had very friendly staff as did the gondola, the restaurant offers a good view from inside but we did not eat there.
Make sure to pack a flask in your coat, for a little reward at the peak too.
This review is the subjective opinion of a TripAdvisor member and not of TripAdvisor LLC.