Spinrite is a serious case of hype. Although it can recover data in some instances (I used it sucessfully, specially in floppies, as some HDD tools don't work on that), it is mostly technological vodoo, promising things it simply can't do. That's why all those scan levels are plain bullshit.
And that's why it is also too slow. Don't try it on a 20GB drive, let alone a 200GB one.
Spinrite is no match for MHDD. In what concerns to recovering data from some bad sectors, it is no match for HDD Regenerator either. Unfortunately, this later one doesn't work on floppies.
You may find a bit more about Spinrite in
http://www.grcsucks.com
Daniel