The H-bars are pretty impressive but are currently made only for the "beamy" PA's. They are a bit too wide to fit a conventional yak.
We have a couple of newly arrived sets in the store. I would love to set up one on a floor display but it requires drilling into both of the black mounting plates. They are plenty sturdy to use as a "pull up grabber" or as a balancing assist while standing. When not in use, it will fold down over the bow and will not get in the way of opening the front hatch. I believe you can find a video on our Mariner Sails Facebook site.
The sidekicks work real good and have several adjustment levels. The complete set consists of two inflatable floats, a permanent crossbar mount (with brackets & mounting hardware), two articulated bars that attach into the crossbar and floats. The sidekick should be able to be mounted on a non-Hobie yak as long as it has a good flat surface for the stationary cross bar. Most of the ones we have mounted have been on Outbacks.