Just a simple hobbs/pressure switch system. This discussion came up like a year ago, the DIY kit was mentioned. I guess for convenience buy it all from one place.
They offer a progressive controller, dont know/havent heard any feedback on it.
I always recommend anyone doing a purchase to contact all the sources where they can obtain the item from, and speak with the vendor. In the end this should make you happy on your decision.
The forums here are another source of information. As is its search feature.
Hope this helps,