Functional "big" group size? Quick question

Hello, I have a quick question. Could you please tell me what is your experience with big groups? I am part of a 30 people group and it works very well (some people on nine.testrun relay and others in our own relay, wich is set as default chatmail I think). So, what size of group starts being slow or disfunctional, please? We are about to create a coordination system for up to 40…? people and it would be great to suggest DC, but it is better to ensure success…

Haven’t seen issues with big groups yet, however, many of the hosted bots start to die if a certain combination of servers are resident in the same group (the probability of it happening grows with group size). It’s definitely a bug in either the code of multiple bots, the bot SDK or core (hopefully not the last).