I have been reviewing several of the different 3d printers on the market. There seems to be 2 different and competing styles. One one side you have the additive which basically builds a model out of an expensive plastic material. One the other hand you have the subtractive design which carves 3d models out of any material that you can fit in the machine and it will quickly carve out the design that you upload. The additive models take up to 10x longer to create the model and the materials are quite expensive. The subtractive is not only faster but there is a wide range of materials that you can use that are very inexpensive like wood or foam. The additive models are less expensive to buy but like an inkjet printer you end up paying the high cost of the consumable which in this case would be the plastic additive material.
Due to the speed and wide range of materials, I am much more excited about the subtractive design.