Strategies for validating WAL-shipping replication

We've set up WAL-shipping replication on one of our database servers,
and the question is whether it runs correctly.  Is there an easy way
to access some tables and see if the data matches (possibly in
single-user mode)?

Stopping replication and starting the server for real on the replica
means that we have to set up things from scratch, right?  (This is a
bit annoying because of the amount of data which has to be copied from
the master.)

--
Florian Weimer                <fweimer@bfk.de>
BFK edv-consulting GmbH       http://www.bfk.de/
Kriegsstraße 100              tel: +49-721-96201-1
D-76133 Karlsruhe             fax: +49-721-96201-99