I use this method and it works well.
Install the rsync utility from the AIX Toolkit CD, on both machines.
Once done run a command similar to this from the machine you want to copy to:
rsync -ruz root@other_macine:/remote/dir/ /local/dir
If you are using ssh, then use the command as follows:
rsync -ruz -e ssh root@other_macine:/remote/dir/ /local/dir
Finally, if you want to cron this then do a public/private key exchange if using ssh or just set up .rhosts on both sides.