I picked up the Weider 40 lb. Cast Iron Weight Set to do some accessory work and they have definitely met my needs. The plates slide on the bar easily and stay in place with a spin lock collar, but it tends to loosen up when I put the weights in motion so I have to tighten them at the start of every set to make sure the weights don't fall off the bar. The bar is smooth, but it still provides enough grip so I don't have to squeeze hard when I'm doing curls, raises, and rotator exercises. The finish on these plates have started to dull a little due to getting wet in a flood, but it has no impact on their standard weight value and performance. The only downside I have come across with this set is that the case provided to house the weights is cheaply made and comes undone when I try to carry it by the handle. I would definitely recommend the Weider 40 lb. Cast Iron Weight Set because the weight is accurate, cheap, and doesn't dig into the hands to form calluses.