I also had a look at the Inventables site and saw their "Pro" range. These use profile rails and ballscrews (although the one I saw used 25mm ballscrews which probably slow the machine down). The price difference is an indicator of what better quality components cost. I also wonder about the life of the routers they use, especially given how long it seems to take to get through thicker timber.

But as an engraving machine, within its limits - horses for courses. There are a number of things about them that I don't like, but that's not the same as saying that they might not suit some users but go into it with your eyes open and not dazzled by videos from people from carefully-selected users!