The idea is great. Especially for stuff like school projects and the like, getting kids involved in computing by giving them the tools to recreate awesome movie effects is, by itself, a nice idea. But we're talking about something where inexpensive is a very relative thing. Of course, compared to the cost of a professional bullet time rig it might be inexpensive. But we're still talking 4-5 digit cost here. Which can easily push the limits for the average hobbyist, let alone something like a school class. I don't know about your classes, but we sure as hell did not have 4 figures to blow on a school project, let alone one that is kinda hard to justify towards some parents.
It remains a nice project, but I guess any halfway decent film maker would probably rather rent some time at a studio equipped with something like that, and everyone else can't blow roughly 5,000 to 10,000 bucks on a toy.