I bought a cheap version of NeatWorks and downloaded a demo of Paperport from Nuance in an attempt to find a good option for digitizing all my mail.
My experience with NeatWorks isn't great. It mostly works, but some problems have cropped up from time to time that make me have some concern. For example, when I first installed the application it automatically searched for updates: it found one, and I installed the newer version of the app (newer that what was on the CD).
Well, it turned out over the next few days that much of the text that it would OCR would not make it into the search index. So when you went to search for some keywords nothing would be found.
I contacted support and after walking me through a bunch of stuff, it turned out that there was a much newer version of the app available (but somehow their auto update didn't find it). This new version seemed to fix this problem, but I basically had to rescan all my documents. At that point, it was only a few, but what if I run into another problem after I have a few hundred scanned documents?
Speaking of a few hundred documents, right now I have 50 pages scanned and my database is 300MB. This is insane!! Even if you backup your data and compress it it ends up being like 500KB / page. WAAAAAAY to large. I guess it really isn't THAT big of a deal. I mean if I end up with 5000 pages (100x what I have now) and my database is 30GB, it will really be stupid, but it won't really be a problem I guess.
Another concern of mine with NeatWorks is lock-in. What if I want to move to some other software product in the future? How can I get my documents out of NeatWorks? Well, it turns out not very easily. You can export each document to a PDF, but you have to do it 1 at a time. If you select multiple documents, it puts them into 1 giant PDF. This is completely useless. If you have 5000 pages and you want to start using some other PDF indexing product, it will take you forever to export all those files. Also, you can only use the software with their scanners.
Also, last night I noticed that some receipt that I had scanned never showed up in my "inbox" (it goes from the Quick Scan to the Inbox). This has me concerned. I got no error message or any indication that something didn't work right. It just never showed up.
Paperport has some nice pluses on its side. It uses any scanner (not just 1 like w/ NeatWorks). It stores all images as PDFs in a folder on your file system so you can manage them as you would any other file.
Reviews for PaperPort were not good, but others claimed the newer service pack fixed a lot of problems. I did have it lock up on me once, but otherwise it seemed to work.
The main problem with Paperport is it is trying to do to many things. NeatWorks is for exactly what I am doing, Paperport is trying to be a fully featured Scanner software product, helping you to manage photos and stuff like that. The UI is pretty poor also.
Basically though, the only reason I can't see myself using Paperport is that there is no way to attach and search by a date field. I don't care about the date I scan a document (the file created date), I care about the date of the document. So when I search for Mastercard statements, I can filter out what I want by date. I didn't see any way to do this with Paperport.
Then when I went to submit a question to their support team asking about this, I was totally convinced to not buy their product (click for full size):

As many users have commented, it really does look like Paperport WAS a good product which has just morphed into a big, bloated, difficult to use product.
UPDATE: Now Nuance has changed me for the full product. I'm guessing part of their trial is that they will automatically bill you for the software if you don't cancel your trial. Wonderful, I am really glad I didn't pick Paperport: time to call and demand a refund.... again (they charged me 8 bucks for some BS extended download service on my free trial... these guys suck).