I've thought about it myself. I'm getting a large group in the spring, but you know what? For a lizard that is so hard to come by, and when you can come by it, they aren't the easiest things to keep alive. I think they deserve a one bedroom condo. My buddy keeps his separate and in not too large of set ups. They are doing great and he is getting good results too. So I'm going to follow his method.
He also told me they are quite aggressive and I tend to believe everything he says. So IMO just keep them separate and get something else cool for that bigger cage.
Just my two cents.
JMorash