I'd have to see the build quality on the 3d printer. FWIW the AxiDraw is pretty robust. You can buy cheap knockoffs from Chinese manufacturers for about half the price but they come with compromises.
Having gone both routes I will say that among the "knockoffs" you can find several that use the EBB Driver Board [0] which minimizes some of those compromises and allows you to use the Evil Mad Scientist tools with a little bit of Python or tweaks to config files.
That said the build quality and software products from EMS make it worth supporting them, to me.