From the 18 months or so that I've been visiting this message board, not one person will tell you that two chams in one cage is a good thing. The only time I've seen people mention multiple chams per cage is when they are talking about newly hatched/born chams. After a few weeks, it's always one cham per cage. I've never had more than one cham, but it seems to me that having two in close proximity (outside of breeding time) will only lead to stress and a shortened life span for both animals. If you actually care about the chams, then it's one cham per cage.