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If you want a good analog-to-digital converter that has a proven track record with iMovie, FCE and FCP, look no further than the Canopus ADVC-110.

Alternatively, you can use most any inexpensive MiniDV camcorder as an AD converter.

-DH
 
As for the first unit (the Plextor), I highly doubt it. Most Mac applications need a Firewire interface for video capture unless the device comes with dedicated Mac software.

The second unit isn't a capture device at all; it's a TV tuner and analog video interface only.

Mac-compatible analog capture devices are limited. Canopus is one of the only companies left that makes one. $250ish for an ADVC110. Honestly, that's about the best deal you're gonna get on a quality capture device that works flawlessly with everything.

Pinnacle also has a $100 product (I think it's called Mac Video Creator), but it compresses everything to MPEG-4 on the fly and automatically makes iPod-compatible video files (definitely not what you want if you plan on editing).
 
I also want it to be able to connect to my xbox 360. Are the ones that you referred to able to work with my xbox 360.
 
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