It is to my understanding the Veritas Replication Exec works at a FILE I/O level, thus each page that is written into the files that it is monitoring, are also written on the other server. It does not use log shipping, or other such methods.
Therefore, the most important factor is that the disk I/O and size can match the production server. If you are not sure if the system can "hang" with the memory requirements, or other such things, you could try a test "failover", let it run for 24 hours, and then perform a reverse replication, and then fail it back to the primary.
There's nothing like a live to test find out what she can really do.