As far as i know the only one on the market right now is the JRSC. Its a great all around setup and i`m am personally seriously considering buyin one. Hytech has posted about one they are making but i think they have put it on the back burner right now. Search and u should be able to find the thread, it has some good pics. If it ever does come out though dont expect it to be cheap though. As for vortech or procharger, they use centrifical style superchargers. This would make it very hard for them to creat a kit for our car since there is no room left on the accesory side of the engine. I supposed the could run some sort of shaft from one side of the engin bay to the other wher there is more room but again there might be some clearence issues. This combined with the rather sophistcated ecu we have makes me doubt one will come out from them in the near future, but your best bet is to call them about it as I`m only speculating. I think i heard somewhere about kenne bell SCs doin some work with hondas but its problly just a rumor as they are reall a domestic company, they do miata stuff though so i dunno.
yea as much clearance issues the centrifugals have...the vortech kit for the Si that came out looked top notch
the installation of the jrsc is much cleaner and more of a bolt on 35% power add on...very slick