Notifications: use Use Single Polling Request or not?

Hello. I read documentation about Notification settings and Use Single Polling Request option.
https://stackideas.com/docs/easysocial/administrators/configuration/notification-settings

But still can't understand what is better for big sites:
1) Use Single Polling Request
2) or Polling Interval (Multiple Polling Requests) 5+ second?

What settings will make site works faster?

Thanks.