it's only a front-end anyway. it basically asks you some questions and then pumps out the cryptic rsync command line command that will do what you wanted.
Rsync itself is a bit of a mess though. it keeps changing its command flag syntax and usage, and custom apple flags and resource fork support has been all over the board. There also tend to be undocumented flags that you need to use as of lately.
And something in 10.6 doesn't play nice with the latest rysnc. If I ditto a volume, I can then rsync to update it without issues. But if I try to rsync from the start (with an empty dest volume) it won't boot, and I haven't figured out why. Something's not getting copied properly.
