My two cents: log the model name (obj-c class name?) and the id, e.g. "LBDevice#1" or "devices#1". This should be enough to lookup any further details in the database (server-side).

I'd rather manually look up model properties on the server than have a completely unreadable log.

Also, since subclasses can always override this, having a potentially less-useful output might stimulate  LB users to override the default description more often.