What calendar plugin to use?

Hello!

Basically what i am looking for is some tops on what calendar plugin to use.

What i need is following:

1. calendar will be list of events
2. i will have several user groups that will be able to add stuff to calendar
3. i need search for calendar events.
4. It should be searchable by location, aka every event needs to have a field “Location” and we need to be able to fillter events by that field.

Thats it. I know there is a lot of calendar plugins and really its a pain to search through them all. So any tip on which to try is more then welcome!

GaVrA