During rush, the fraternities you visit should be informing you of the benefits of that particular group. If a fraternity talks more about its competitors than itself, be aggressive and ask about that group.
Little progress is make in condemning another organization.
Perhaps most important, make your decision on your own. Even though your best friend or the group you attended rush parties with have decided on a particular fraternity, you do not have to. Your friends should always be your friends. The choice of fraternity is completely yours. It is a decision you have made for a lifetime.