Postgres streaming replication between hosts with different timezone

I am running Postgres 9.1 on Windows 2012 servers. I am using postgres's streaming replication to replicate data between 2 servers.

It has so happened that the time zone of the slave has not been set correctly. The master time zone is UTC+4:00 where as the slave is on UTC-5:00. The master time zone is correct whereas slave timezone is incorrect.

Would like to know -

1) what will be the effect of this on fields of type "timestamp with timezone"?

2) what will be the effect of this on fields of type "timestamp without timezone"?

3) what will happen to replication if we change the slave timezone?

Thanks for your insights.