Personally, after being a member of the Miata forum for almost 10 years I've seen these deals come and go.

There was an on-going "dialog" between Fast Forward and Corky about superchargers. Last I read Corky had not finished his unit.
I guess they got their turbo working: My thanks to Corky, Stephanie and Brain - MX-5 Miata Forum

Then there was the outfit using a ROTEX turbo that came and went. And the Miata community is huge compared to the Crossfire. These guys are pushing 17psi and up. 250hp out of 1600 and 1800cc engines. Lots of cheap Miatas out there and lots of young guys who want horsepower.

What I'm saying is a lot of these "kits", in my personal experience, have turned into vaporware.

One of the biggest hurdles for California drivers is having the unit CARB approved.

I'm not bad-mouthing BEGI but I am thinking he and others tend to spread themselves pretty thin with multipul projects.