The 864 has the same data compression modes as the old BR8 - MT2, LV1 and LV2. The max time on a 128meg card compares with the BR8s original 100meg zip.
I think it was shortsighted not to include the VS840 MT1 mode, which is significantly cleaner. Thanks to the demands of the Digital Camera market, Compact Flash cards are getting bigger and cheaper all the time. In a few years, 1gig cards ought to be at "pocket money" levels (128meg already is - Boss aren't being that generous). So not only is MT1 feasable, but uncompressed recording too! It's interesting to realise that the original VS880 shipped with a fixed 540Meg hard drive and the FX was optional.
However it shapes up - it's got to be better than cassette tape.