I found this nice vase on Thingiverse and printed it at 75% scale a couple weeks ago.
It came out pretty good except for the area near the bottom where it was overhanging. 3D printers don’t handle overhangs without support material very well. I tried reslicing with support material added, but didn’t like the way it looked in either Cura or Slic3r so I didn’t try to print it again.
Then I tried printing it upside down- the overhang is much smaller.
About 12 hours later, here’s the result: perfect!