This is the SOFTEST spring rebounder on the market with its patented spring loaded legs. If you need a soft rebounder, this is a great one to get. You will want to wear shoes while jumping on this rebounder. This is a much different feel than a circular rebounder. I have sold this rebounder without a single return. It appears that having the shock absorbing legs, they got around not having the spring absorb all the impact which means you don't have to change springs as often to maintain responsiveness. This eliminates having a longer coiled spring that stretches out too much that gives fewer bounces per minute. If you tap on the springs with a spoon you can definitely tell if the springs are made of the same alloy used in standard 3.5 inch springs designed to stretch for a soft bounce.
This rebounder is innovative as it gives a great bounce. Being square definitely gives it a different feel, especially near the corners than a round model.
As long as you know what to expect when getting this rebounder you should have no problem with it.