As Matt said, it will help in training. But, it won't make the boat perform better.
The reason is that there is no way to get luff tension on the jib. It attaches to the spreader with the halyard running to the mast turning block. If you put much load on the halyard you will bend the spreader bar.
As a result the jib will not let you point as high upwind and will only be a help on a close reach to broad reach. I might help in tacking, but the boat normally tacks so fast you don't need it anyway.

By the way, No one is knocking the quality of the Hobie Factory sails. It just happens that this jib kit is not effective in making the boat perform better. Same with the spinnaker.

In Wave racing throughout the country the Hobie sails are winning lots of races against the after-market sails.
Rick