I've used SCSI and Fibre Channel drives for years.
I've wasted a few moments here and there with IDE.

SATA is NOT IDE. Combine SATA drives with a decent
3Ware controller and they will outperform almost
anything.

Their native streaming read rate is about 20% faster
than FC, while their seek time is a bit less, which
a good caching controller will "wash" out.

My Bonnie++ tests showed my dual opteron with
6 SATA disks and a 3ware controller outperforming
every other system in my computer room, including
some 3 year old high-end FC gear.

When I then tested against my brand-new EMC CX700
with stacks of 140GB FC drives, I found that the
3ware SATA controller was a bit slower for writes,
a LOT faster for reads, and a bit slower for seeks.

But this merely meant it wrote a measly 300MB (that's
megaBYTES per second) while reading at around 170MB
per second. As compared to the EMC writing 380MB
per second and reading 100MB per second.

I started running multiple tests at the same time,
and found the degradation to be very graceful.

I will very happily use SATA for the majority of
my work in the future. The only reason I don't
have it now was the EMC CX700 using FC disks was
cheaper than the IBM using SATA, plus more heads
is better for seeking. Also, I got 2 CX700s, which
meant 4 times the FC <-> switch connections. If
I bought the IBM it would be a single system with a
measly 4 wires coming out.

Right now my home PC uses 250GB SATA disks. I NEVER
feel like I'm waiting on IO.