Acrylic is more for the show, and does bow, but if you want to have your tank look really good, I do reccomend Acrylic over glass.
Acrylic is light, more expensive, and gives a show look to your aquarium (IMO).
Glass is just too heavy...
But that is off topic...
About the glass cages... I have not bought and havent thought about buying from them for awhile...
I have heard that most of their tanks tend to get cracks in them after awhile of holding water and sitting there...
I would probably either reccomend going with tenecor.com or seeing what good deals you can find in your classifieds or ebay.