I bought one of these to scan in a bunch of old documents such as tax returns from the late 1970's.
It has a lot more features than you would expect from the box and marketing information. With the Scanner Toolbox software you can easily re-program the three function buttons simply by selecting the new function from a drop-down menu. I set up one button for PDF.
I bought this in November 2007 and have not tried the latest software.
The 2007 CD included software not on the Canon website. PhotoStudio 5.5 editing software that came with it is okay and was ArcSoft's latest version. PS 5.5 does have one neat "auto fix" feature. It displays about 10 alterations simultaneously so you can choose the best one.
You may have trouble getting the colors on pale colored documents (such as tax returns) to scan properly. They may look washed out or even disappear, leaving a white background. This is because the Scan Driver has an Auto Tone feature that defaults to ON. The Unsharpen Mask and Auto Tone feature cause MAJOR changes. You can mess with them in Preview mode. Run a Preview scan and then just select the various features and it instantly updates the image. One thing I particularly like is the Text Enhanced scan mode, for (black & white) documents with some faded text (typewriters, multi-generation photocopies, etc.) It basically leaves the background normal but darkens any text.
The scanner is about the same size and weight as a laptop computer, which means it can fit together with a laptop in many laptop carrying bags. It is mainly plastic and glass for the scanning bed, so it would need to be treated with the same care as a laptop.
Scan rate for colored images (tax returns) does seem a little slow. If you will be doing a LOT of scanning on a regular basis you may want a faster scanner, but may lose portability. Depending on the type of scan (color, etc.), the unit can emit a high-pitched whine. It's not REALLY loud but could not be used, e.g., while listening to a lecture or in a library. This is not a malfunction, it is because the motor actually starts and stops constantly to move minute amounts. If you REALLY needed it you probably could run the scanner IN a briefcase to kill the noise.
The Scanner Toolbox software lets you choose your output software. So, for instance, it scanned tax documents, generated a PDF and I set it to transfer PDF's to Adobe Acrobat instead of Adobe Reader. You can choose your OCR, image editing, and PDF software.