Imahashi machines are very common in South East Asia, numerous
examples can be seen in the Bankok cutting houses. They are extremely
well engineered machines with excellent repeatability. I have used a
friend’s in Australia to cut several stones and found the transition
from a conventional mast machine such as most of the American models,
to a platform machine, which the Imahashi is, to be no particular
problem. Your friend’s comment on the importance of stability in the
mast is absolutely correct but is not relevant to the Imahashi design
where the faceting head sits on three mounts on the platform and the
entire handpiece assembly is picked up off the machine in order to
inspect progress ie there is no mast.
The other particular advantage the machine possesses is that you can
obtain both a faceting head and a cabochon head for the device, given
the strength of the yen and the current price of the Imahashi this
could prove advantageous if you decided to go down this road.
I was impressed with the machine, but not sufficiently so that I
would abandon the mast type Halls machine, ( sold in USA as an Omni I
believe) I mostly use.
I also trust that my response does not evoke countless replies
either decrying or supporting the merits or otherwise of the two
design types, my limited experience tells me that any machine that
can cut and polish with a high level of repeatability is all that is
required, the rest is simply personal preference.