<?php if (current_user_is("s2member_level1")){ ?>
	Content for Members at exactly Level# 1.
<?php } else if(current_user_is_not("s2member_level4")) { ?>
	Some content for those who are NOT at Level #4.
<?php } else if(is_user_not_logged_in()) { ?>
	Some public content.
<?php } ?>