The reports of the demise of the test cube are, perhaps, premature. I’ve read people saying that new firmwares and versions of Skeinforge make test cubes unnecessary, but I’m not buying it just yet. To be sure, one can get a lot closer to a usable print quickly, but there’s still plenty of room to screw things up.
I don’t know why I keep all the old junk. Maybe to keep my humble. Maybe I hope for a recycling option in the future. Still, in a weird way, I like to see how far I’ve come and what I’ve learned from all this fail.
I also have a box with failed prints, good to look through it if you’re not satisfied with the current quality of prints you’re getting.
About test cubes, I can confirm I’ve only printed a single test cube since starting with skeinforge 41 / volumetric 5d. And that was only to test the squaring. The prints you get are so good they are usable almost right away, so I prefer to print prusa bar clamps and endstop holders when I’m tweaking something.