The Digitizer and similar scanners like the Sense are not going to give you highly accurate results. As a general rule products in this price bracket will be in the 1mm tolerance range so if you're scanning highly detailed items, particularly small items, then you won't get an accurately representative scan. My opinion is that these type of scanners are best for organic shapes.

If the above is the type of work/hobby you do then I highly recommend spending a little bit of money on a CAD program. Please look at Moi3D and 3D Systems Design. Moi ($295) is a nurbs surface modeller and 3DS Design ($129) is a parametric solid modeller (used to be Cubify). Again, highly recommended.