Calendar plugin with working feed?

Can anyone suggest a couple of calendar (events) plugins that have a working feed, so that you can view them in Google calendar, and other calendars?

I tried most of the recommended ones, but at best the events get imported when you first add the link or ics file, but none of them reflect the newly added or updated events in Google calendar. Some work partially in Outlook (meaning I got them to at least once update after the initial adding), but I haven’t been able to find a single one that integrates into other calendars completely.