Rated 3 out of 5 stars

I read the FAQ but fake email addresses are ugly, the search will contemplate these addresses... other extension do not add fake addresses...
Moreover multiple address book feature DO NOT works with multiple Google account. The OAuth authentication is done for the first account configured, other accounts will never syncronize. This is probably a bug. Can I help in some way to fix it?

This review is for a previous version of the add-on (2.0.4). 

I agree they are ugly but the alternative is a broken address book. You can sync groups with individual address books to work around this. I'm also considering an option that would not sync contacts without e-mail addresses in version 3.0.

Multiple address books with multiple accounts is working fine for me, but you may have hit a bug that I haven't found yet. Could you turn on Verbose Logging in the preferences, try to sync, then send me the log? http://www.pirules.org/extensions/submit_error.php?ext=gContactSync