Edison Cube. Super frictional to turn even if tensioned loosely, and looser tensions would generate edge pops galore. The cube was more likely to lock up than turn for any given rotation. To make matters worse, removing the center caps to access the screws was difficult, so desperate attempts to re-tension the cube were exercises in frustration. The cube is also ugly with dull, low-contrast stickers (which chipped and peeled readily). The icing on the cake is that the Edison cube was one of the most expensive cubes to obtain (~$20, which was exorbitant in 2010). I remember being very excited to import my Edison cube from South Korea, very impatient to receive my package after it shipped...and very disappointed when I could barely turn the thing out of the box.
