For those of you who are not familiar with the RepRap project I would suggest getting a little more information from their website: www.reprap.org.
The basic premise is to great a machine that can replicate itself. Therefore the majority of the parts on a rewrap machine are plastic that the machine can then print. This allows for printing of another rewrap for a friend and/or allowing for continuous upgrading.
I started with a TechZone Huxley. I would not recommend it at all. If you're even considering it, head over to RepRap Forums. This post will explain the difficulties associated with this company and this design.
The Huxley is a smaller RepRap with a build size of approximately 100 x 100 x 70mm. It is also supposed to print at higher speeds due to the lack of a stepper extruder on the X access, thus decreasing weight. While this is true, the use of a Bowden cable, (See reprap.org for explanation) decreased print quality significantly. Subsequently, I attached a direct extruder to my X axis, decreasing X axis length and Z height. I chose quality over size. It allowed me to print out a replacement Prusa Mendel which I am assembling currently.