The SawStop table saw itself is a high end tool, pricey, from $1800 for the simple Contractor version to over $2500 for shop cabinet saws... $70 is for the stopper cartridge, plus blades I and others use may aadd another $100 to that... And now Sawstop is trying to push their way into places that may just can't afford them, schools, other public institutions, so it looks to me that their marketing team has taken over... Not without opposition...

http://toolmonger.com/2012/09/14/more-sawstop-bs/

So for the homeowner, hobbyist it's out of reach most likely, there are no retro kits, much less adapters to long time manufacturers like Delta, Grizzly, etc.. My saw is a 1940s Walker-Turner 10" cabinet saw, in great shape, in no danger of being replaced...

While it is great technology, to me it's more useful to teach safe operation, maintenance, than to rely on maybe letting the users guard down... I had one incident as a 15 year old when I had made up my own small saw, I got careless, the blade tried to take a divot from my thumb as I reached over, lesson learned... many decades ago...