Besides the cham not being able to find food, and not being able to find adequate lighting, also note the effects it could have on your room. Remember, being a larger enclosure means that you need to work harder to keep the humidity up and the temps right. IE alot more water and lighting. With my mellers cage (4x4x6) , just keeping the humidity at the levels it needs to be, brought up the temp in my room 7 degrees and the area around it is wet most of the day. Besides the stuffiness and the possible wall damage, it could be great. Just remember to not go overboard, as it will become a larger a chore than it has to be.