I really like the idea of the metalicarap, in that it gives access to normal people, the ability to print metal objects. However i do have to ask why the design is so big. While a 30cm x 30cm x30cm area might keep it in line with the other reprap's the cost and total machine size is still quite big. Now i'm not saying eventually making one this size is a bad thing but there are many uses for a much smaller design (5cm x 5cm x 5cm for example). A smaller design should be easy to make, cheaper and more accessable while giving you room to reiterate for bigger sizes at a later date.
For example one use of this would be to print unique jewelry. A ring dosn't take up much space so the larger version wouldn't be needed unless you start to mass produce the ring. So the smaller one would be best for initial small scale production. If you go to a more practical area, small titanium implants wouldn't need a lot of space, for example dentists could use a small version to make implants design for patients, either current types or even possibly a full on titanium root replacement for a removed tooth. For example the dentist could remove the old root, scan it in with a 3d scanner, do a bit of processing, print a new root out and implant the titanium root the next day before any significant healing takes place. They don't need a big version to do this, in fact several smaller ones would be preferable.
A smaller version might also be easier and quicker to make, for example a smaller vacuum chamber would be easier to make as the strenght required on the chamber walls would be less. It also means that you can take a working design and find potential problems easier on scaleup.
Its current 1m beam tube lenght is necessay so it can cover the whole 30cm build area while being within the divergence angles in existing inter lens deflection electron beam welding guns, so MetalicaRap remains compatable with existing commercial gun technology , and so people have the choice to follow that route if desired. Electron beam welders beam deflection was only inteneded for minor alignment.
Once systems are up and running I am sure minaturisation will happen (just like what happened in tv tubes) and many build areas with or without electron beam windows will follow.