I don't about the other ones, but giving you extra when you get someone else to join is unethical. MCI started this trend with their "friends and family" promot

I don't about the other ones, but giving you extra when you get someone else to join is unethical. MCI started this trend with their "friends and family" promotion, and it really pissed people off. People who don't use the system hate being pestered by friends and family to join something they don't want or need.