What’s the max number of guests active on a single board without affecting Miro performance?

I see this post on over 300 https://help.miro.com/hc/en-us/articles/360013912300-How-many-users-can-collaborate-on-a-board-simultaneously 

I’m working with people in developing nations that may not have the latest in connection and equipment. I’m wondering if there’s an advisable upper limit where the experience is no different from only having a handful of users.