Jim, does SpinRite work well on modern/large SATA drives?
And what about USB external drives - have you tried SpinRite on any?
I don't have SATA drives, but according to Steve Gibson's FAQ
http://www.grc.com/sr/faq.htm the answer is yes. I've used it to examine (haven't needed to repair) USB drives, and that works.
I've used SpinRite since version 2 a hundred years ago, with early PC compatibles; it's remarkable what Gibson's gang has developed in this product - his knowledge of the low-level hardware of drives and controllers is comprehensive and SpinRite can really dig into them. He's always preferred to do his final coding in assembler for speed and control, and it shows; his products are incredibly tiny by today's standards of code bloat. Used to run into him at Comdex years ago and he's the real deal - an ubergeek.
As long as I'm hyping his stuff, if you go to his site
http://www.grc.com/default.htm and scroll down, check out ShieldsUp in the Hot Spots section - it's a free interactive test of your firewall and system port security, and will nondestructively bang hard trying to get in with a report on what holes it found. I've had to set up some fairly complex VNC and camera remote access for my business, and used ShieldsUp to batter my port-forwarding and firewall setup afterwards to make sure I didn't leave any hacker-holes open by mistake.
GRC.com is highly recommended for education about system security, disk-drive reliability and many other topics, even if you have no interest in his products.
When you see that in order to produce, you need to obtain permission from men who produce nothing - when you see that money is flowing to those who deal, not in goods, but in favors - when you see that men get richer by graft and by pull than by work, and your laws don't protect you against them, but protect them against you - when you see corruption being rewarded and honesty becoming a self-sacrifice - you may know that your society is doomed. - Ayn Rand