public function getBests($friends) {
		// Make sure we're logged in and have a valid access token.
		if (!$this->auth_token || !$this->username) {
			return FALSE;
		}

		$timestamp = parent::timestamp();
		$result = parent::post(
			'/bests',
			array(
				'friend_usernames' => json_encode($friends),
				'timestamp' => $timestamp,
				'username' => $this->username,
			),
			array(
				$this->auth_token,
				$timestamp,
			)
		);

		if (empty($result)) {
			return FALSE;
		}

		$friends = array();
		foreach((array) $result as $friend => $bests) {
			$friends[$friend] = (array) $bests;
		}

		return $friends;
	}