If you're looking to have speech for ALL people at once, you're going to want to use Teamspeak. Skype has has too many connection issues in conference calls that exceed 3 people. In my experience over the years, Teamspeak has never had these problems, and is less of a pain to create several different rooms and managing members is a LOT easier. I used to manage 5 different CS clan teamspeaks in the past, so I can say for sure that the operations are much better.