Whilst I would agree with the reports that flip-pal is an excellent bit of kit and very versatile
You don't store images to a memory stick but to an SD card (which is supplied along with a usb SD card adapter)
Images can be scanned at 300 or 600 dpi and the flip-pal also comes with stitching software so you can scan overlapping images of a large picture, then stitch them back together again
Flip-pal uses 4 AA batteries and is stand alone
I also use a digital camera but the flip-pal gives superior reults