depends on if it's hackable like TiVo. If it is and you can transfer the programming onto another hard drive, you might as well get the cheaper of the two and then spend the extra $100 putting in a bigger hard drive. For under $100, you can get a good 200gb hard drive.

EDIT: just read the link above, and for $100 more you might as well get the $599 for all the extra goodies that come with it and hack that one.

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