Impressed by the display, and disinterested in non-AC-powered use, I am
considering the new Sony Vaio laptops from a performance and
reliability perspective, and wondered if users here had any anecdotes
or insights...

Sony document the RAID support in the Vaio AR21S:-

# 200 GB Serial ATA 5400rpm hard disk drive (2 x 100 GB, RAID 0 and 1
supported)

This spec, for the flagship notebook, leaves me with several questions:

* How does a single SATA 5400 drive compare in terms of latency/IO
bandwidth with, say, a 7200RPM ATA drive which I'm using on my old
laptop?
* Neither RAID 0 nor RAID 1 is an ideal fit for my pattern of usage.
For arguments' sake, say I've got 20GB of 'critical data' which would
be very time-consuming (or impossible) to recover in the event of a
drive failure... and anywhere between 80 and 120GB of 'temporary
data'... much of which is likely generated by compilers, but also
including caches of data held on servers and reference copies of data I
already have on DVD. Do these laptops support "Raid0 and Raid1" (in
any combination I choose) - or should the advert have actually read
"Raid0 _or_ Raid1"?
* Is it possible (and/or advisable) to use the two drives separately?
* Is the raid done in hardware or software... If the latter, is this
just windows 'data-striping'?
* Can anyone offer empirical data for drive latency on these laptops
for Raid 0 and for Raid 1?
* Does anyone know the exact drive model etc? I've had recent luck
with Seagates (with 5-year warranties) but I have been burned twice by
IBM/Hitachi drives failing in the last couple of years with my current
laptop... I'd like to verify that drives are end-user replaceable -
especially as, there being two of them, I'm more than twice as likely
to get at least a drive failure with this Sony model.