I'm a little puzzled towards this hardware vs. software RAID,
and worrying about computrons (aka CPU speed).
For all the .*n[i,u]x's out there, the software RAIDs are
pretty damn reliable. If you have reliability problems I'd
dare say it's elsewhere. Hardware gets you more performance,
but you really have to need it.
Second, CPUs are just stupid silicon office products, they
are SUPPOSED to work hard. Who cares if would like coffee
breaks? I think most people also grossly overspec CPU, because
(1) it sounds cool and (2) they don't really know what's needed
(caveat, it's so cheap to overspec it's a perfectly valid
approach, but no sense losing sleep over it).
I build and run servers for a living (not exclusively) and I can
tell you that even a crappy 100MHz P1 does a LOT of work with
just decent hardware and enough memory. A gigacycle CPU with
512M, two EIDE channels, a real operating system, does REAL work!
Mailman is slow because it's bloated, but a lot of software
today is like sausage, I'll eat it well-cooked but refuse to
look inside.
You might as well get your money's worth from these cheap
capitalist products, and don't worry about the needs of
marketing. Big disks and more memory, you can hardly go wrong
(or cheaper).