Brad,
I think it depends on the temperament and sex of the lizards that you are putting in there. For example I've got what I think is a dwarfed beardie and she is in with a few adult males and some other juvenile females and she is fine with them - it just really depends on the temperament. And I guess the other thing is to make sure it's not too small - otherwise if it gets walked on or whatever (which commonly happens with my little beardie) the weight may injure it. And I guess also make sure that you dont end up with a dominant male beardie dragon and a dominant male pygmy - that could make for a disaster within the one enclosure during breeding season.
Hope my advice helps.
Kelly