One thing I am certain of is that the Solidoodle is a home-brew 3D printer, and comes with all those problems. It is definitely well made, and it would be hard to beat the price for the quality it produces, but the difference in price seems to be primarily software support.
To run the Solidoodle, you need to use Skeinforge to turn 3D models into print files, then use a crude printer interface which is a set of Python scripts to make the printer work. Inside Skeinforge are several hundred settings which you can tweak to get better quality.
Admittedly, the Solidoodle comes with Skeinforge pre-calibrated, so you don't need to tweak it to be able to print rudimentary things. However, printing with no calibration leaves many little "whiskers" of plastic, which are a result of plastic continuing to extrude when it pauses. For example, here is a Yoda head which was printed with default settings. You can see that there are many little hairs and bumps on the ear that are a result of the printer being calibrated incorrectly.
I certainly do not want to disparage the Solidoodle company or the developers of the Skeinforge application: The Solidoodle printer is very good quality for the price, and the Skeinforge application is a very impressive application.
Still, I bring these issues up to show how 3D printing is still in relative infancy. There are not well-developed interfaces to make printing easy. There are not well-developed algorithms to make calibration easy. There are not well-developed work flow methods–to print an object, you must open Skeinforge (a difficult interface) and figure out how to compile your model to "GCode", and then you must open the print program (another difficult interface) and figure out how to start it printing.
With all that said, I would like also to let you know the feeling of awe that I got when printing!
Watching an empty printer bed be filled with a thing like the Yoda head was incredible to watch and, even despite the frustrations of dealing with early-stage software, it was well worth the time and cost.