Hi James,
Several years ago I also had a gob of items to scan and I was lent a FujiScan scanner (don't remember which one right now) and for my purposes, it did fine. Actually it did spectacular because before I was lent that scanner I was doing this on a flatbed. ('Nuff said.)
What I did want to add to your information was one particular discovery: The FujiScan would both scan AND OCR each page (both sides) all at once in a very fast fashion. However, I found the quality of the OCR was not very good and the storage size of the documents was very large. So, what I did was to scan away like crazy and at the end of the day I'd point Acrobat to OCR "that folder" of images and go leave for home. When I got back they were all done and I then started the next day's activities.
To get high quality OCR, there are two things to consider: One is scanning, please be aware that faster is not always better. Faster typically means lower resolution and for quality OCR, higher resolution will give better results. If you have letter combinations such as "ri," a lower resolution may cause this to show up as "n."
The other thing to consider is the quality of the OCR software and Acrobat's is very good. FujiScan not so much.
So yes, you have a gazillion boxes to scan but having a machine do them in top top top speed may not give you the results you want. FWIW, I found running the scanner at 600 ppi did make it run a bit slower but increased the accuracy of the OCR significantly. But, as I was referring to, Acrobat is not fast when it processes the pages and it has a VERY ANNOYING habit of popping to the top of your screen after each page. So trying to do something like reading email became almost impossible and that's why I'd stick it to end of day's activities and go home to let the machine do what it needed to do.
If money is no object and speed is important, but several of these machines, higher some part time folks to crank them away and then, if you no longer need all of the scanners you get, donate some of them to a local charity. They will be grateful.
Hope that helps!