Never been over there, so I dont know what your climate is like.
Like jack said, you could always cover the sides of the screen cage if its not humid enough. So I dont see a problem with you getting a screen cage, since it could be modified fairly easily.
We use the heat exchange to our advantage. The heat is what pulls air through the cage, leaving at the top, with fresh cooler air coming in through the bottom. In my experience, you can keep a completely different enviroment in a 2x2x4 screen cage, than that of the room its in. Just takes the right things to keep things adjusted. Cool mist humidifiers, mistings, plants, covering the sides, different heat bulbs, different ambient room temp, are all adjustable variables that can be played with to get things right. Just a matter of "playing" with it.