We use DocuPen.  The concept is good, and it produces a fair image where copies cannot be made, old plat books, etc.  For day-to-day use, we found that the image quality is too unreliable.  Sometimes, it looks 80% like a photocopy; other times, there are squiggles and beaks in the image;  and other times, other problems.  To use it, you must be very slow, patient and methodical.  Even then, you can come back to the office with a pen-full of images, ready to put together your report, only to find that half of the images are no good. It would be best to download images to a laptop then-and-there, to assure they are legible.  We have saved enough money using it to justify its cost, however.  We bought top-of-line for around $300, for all add'l software, color capabilities, etc.  We bought ours from the manufacturer, Planon, which has a website, and are nice to work with.