I debated and debated, but took the plunge on what I had in mind: a 240GB SSD as a scratch/staging volume, a 1TB HDD as a primary storage device, and two more 1TB HDD as rotating backup devices, all Firewire 800. I also picked up diglloydTools, and I'm incorporating "Integrity Checker" into my workflow via some scripts. Most of the scripted magic is still in (rapid) development, but the general concept is:

Copy the memory card to a designated path/folder on the SSD, and set the memory card aside for safety.
Generate an integrity checkpoint file per folder on the SSD.
Copy the folder from the SSD to HDD1.
Copy the folder from HDD1 to HDD2 (either 2A or 2B, whichever is connected - they'll have a physical sticker to denote 2A/2B, but they're both formatted/named HDD2).
Perform an integrity check per folder.
If the integrity check is successful, move the memory card from "safety hold" to "ready to format".

The fun is now writing the scripts to do the magic in an optimal manner...lots of geekhood going on to analyze the ideal process. More in a week or so.