Contacts Setup consequences

[Age Bosma <agebosma gmail com>]

Hi,

One gets presented with the Contacts Setup when launching Contacts for 
the first time. The question is asked where to keep the address book. It 
is, however, unclear to me what the consequences are of choosing either 
"Local Address Book" or "Google".
It would be nice to have all Google contacts available on my system, but 
I'd hate to see those contacts getting all messed up online.

Situation:
- Running a clean install of Ubuntu 12.10 GNOME Remix (x64)
- Several "Online Accounts" have been added (Google, Facebook Windows Live)
- In addition, several more accounts have been added to the 'other' 
"Online Accounts" (Jabber, ICQ, IRC)

Not knowing what will happen when choosing either option leave me with 
the following questions:
1) Will all contacts, Google as well as those of the different IM 
accounts, get listed in either case?
2) Will the Google contacts be available offline if Google is the chosen 
location?
3) When altering a Google contact online and locally, will it be kept in 
sync in either case?
4) Will the IM accounts contacts be added as separate contacts to Google 
if Google is the chosen location?
5) What will happen if separate contacts are combined if Google is the 
chosen location?

Yours,

Age Bosma