The 5 pair version is a bit flimsy and has an annoying top bolt when assembling. But it’s very space efficient with a tiny footprint.
The 8 pair version is MUCH beefier and thicker steel, heavier, taller, with a bigger footprint to boot. Its main benefit (both versions actually) is that they are appropriately sized to fit round urethane dumbbells, not just the smaller hex style dumbbells. I didn’t use the base and just mounted it with bolts and washers to the middle of my 6 post rack. Ultimate space efficiency achieved.
Performance
Value
Build Quality