A reliable 3D printer > experimental 3D printers at DMS it would be fun to build though.
A while back I dreamed of a scara machine using high stiffness carbon fiber rods (I.e. ~1" dia). A z axis that ran up and down the wall with a rack and pinion and a pair of steppers mounted to the Z, one spun the first joint and via a belt the other spun the second. All the end effector wiring could be run down the inside of the rods. I couldn’t get it sorted without some special gearboxes so I dropped the project.
Anyways, I’d be interested in seeing a scara machine happen, even if not for 3D fab.
This was one of my favorite designs I was looking at, and his Simpson Delta printer design. I met the guy who came up with these RepRaps at MRRF a couple years ago, he had a scara arm at an angle https://www.youtube.com/watch?v=_VUBGYtn36w he’s had some pretty amazing designs.