file system integrity

[Seth Benjamin Rothenberg]

My department will soon be buying a large UNIX box (Vax 5400/5800 or TI
1000 something).  TI says the file system is secure - i.e., you
could turn the machine off and on again and no files would be lost,
and you could log in immediately.  We seem to understand from DEC that
we would need to run fsck before we could log in, and that this requires
10 minutes per disk.  We have 12 drives.  We don't have 2 hours to spare.

Does anyone have any idea what these people are saying?  i.e., did DEC
write an implementation that doesn't use checkpointing and flush()?
(These would ensure that what's to be done will get done, and what has
been done was written to disk)
Thanks
Seth Rothenberg
sr16 at andrew.cmu.edu