Another option is to use the Ardour (
ardour | the new digital audio workstation ) workstation on a mac with an RME MADI card for I/O. Depending on what type of I/O you need, this could be way cheaper.
Ardour syncs really fast and well to MTC ( reportedly within +/-60 samples ). It has a really solid destructive record mode, and of course you can expect file deletions, etc to work on your Mac :)
If you need more horesepower you can get the same thing plus 9pin/video sync, more I/O, and factory support from the Harrison Xdubber (
Harrison X-Dubber ). This is a turnkey product for film dubbing. Not sure if that's what you need but since this is the Post forum.....