Good point on the filament. The value proposition for the Cube 3 doesn't seem too compelling given the price premium on material. Filament quality is a big factor in printing results, but I have no idea if their filament is 4x the quality to go with their 4x price. $1k for a fully assembled, high resolution 3D printer is also a nice thing, but I suppose that they are expecting to cash in over time with their filament sales.
There are so many options out there, that is for sure. Certainly, I would rather have the "problem" of having to choose from "too many" options than not having enough! A DIY one would be both fun to construct, and mechanical failures are probably fairly common, so knowing how to handle those is valuable as you mention.