The cage at the second link, is meant to be an expansion to the cage at the first link. So you have the first cage (the one being reviewed), then you set it on top of the expansion piece and attach the drop in pan to the bottom of the expansion piece. So it becomes a 33" tall cage by 24 inches wide, by 18" deep with 2 full floors and a balcony. The expansion is not a stand alone cage. Hope that helps clarify it a bit. I would probably never do that for a hamster, but I would for rats.
My Syrians are bigger than some of my female rats so I've never had a problem with the bar spacing. 
For my dwarf, I use another cage that I lined with 1/4" x 1/4" wire. (I use the same for my mice as well.)