I've looked at the xante oki printers a few times now. In my view they are unique but the niche they fill is quite specific. For me, one would be handy when the job is to print quantities of 5 - 150 event rack cards heavy card boards / signs / etc. Or when doing a run of mail merged envelopes in the 100 to 1000 quantity.
What other option is there if you want to print small quantities on 500 gsm board?
An example would be signs that don't need to be mounted on separate foam/board.
Or if you want to print 47.5" x 12.9"?
On one hand it's 3x to 4x the cost per print of Xerox, KM, Canon, etc. contract printers. On the other hand, it's 8x cheaper than running the prints on a large format epson or hpz inkjet printer. An example of this niche would be 100 short-short run dust jackets.
So far though, it would have been really handy for a few mockups that I've done recently, and I've looked at it when two or three of these "niche" short run projects have come my way where it was either thick stock or a dimension over 19", small quantity, and fast turnaround since I don't have a solution for them at present; but I don't have enough of them to make it profitable for me to have one to date.