I have 3 sets and they are horribly designed. They can barely keep the figure standing even with the pegs (which they do have). They are also incredibly awkward to display and take much more shelf space than they should. Their 'linking' ability is also pretty horrible.
It's cheap enough to make it worth buying one set to try it out as the paint finish on the Grayskull stands is actually pretty good but that is the only up side to them.
The Snake Mountain stands are horrible beyond believe and even more useless so avoid at all costs. They really cheapened out on the paint job for the final product so not even that makes them worthwhile.