Hrm... I was pretty concerned about humidity and then I noticed the rails encompass the top of the tub. So check there, but what about the temperature, with that much area open the heat is probably going to end up difficult to keep up.
Not sure where the heat is on these. Because the tub isn't clear it will be hard to convince newbies to go for it (most of the decisions to house in aquariums are motivated by a desire to watch the animals). Hrm... depending on heat retention, these may be fairly decent to convince people to swap to after they have had serious difficulties