Look, I love Montreal, but the view is probably better of the tower from the ground than the ground from the tower. Montreal just isn't the greatest skyline, and is the bank of Montreal really that much of a landmark? Maybe I don't understand the city, but most of the landmarks they note are totally not noteworthy to me. It's 10 dollars extra with your biodome ticket, and while I couldn't say it's actually worth it to go, it's probably worth it just to say you did.