Just 1 question: Some servers use TFAR, which can be really nice and add to the experience, but there are also a lot of players that don't use it when they join and TFAR removed the vanilla VOIP from working, therefore they cannot talk, only type. Just something to think about!
In short:
TFAR = Bit more hardcore but requires people to use Teamspeak and not everyone knows how to use TFAR, can be confusing.
Vanilla = Anyone can talk but obvioulsy not as "realistic" and proxy comms are trash in Vanilla Arma (SUPER QUIET)