[ERA Chas]

Sierra bought a company called JFZ in the late 80's I believe. That's the exact same 4 piston caliper as the original JFZ.
-Which were originally sold by ERA as the big brake kit with a 12.1" modified Mustang rotor.
The Wilwood Superlite series is not much different than the JFZ / Sierra.
Larger-yes but the same basic tech as a 60's Cup car. So don't fret that's it's an unproven design or bogus company.