MAS has been around forever... I have car mags from the 70s with MAS advertising fiber parts, including the Mav spoiler way back then. JC Whitney used to carry them too. JCW never puts the brand names, or didn't back then, but the list of parts in the JCW catalog was identical to the MAS list in the mags. They even carried 1 pc fiber front ends for our cars. Don't know if they still do tho.
This may be slightly off topic, but I used a simple straight flat spoiler from a 91 regal on my car. Then again, my car is a 65 falcon, but I would think the core support where it mounts would be similar. It helps push a little more air over the radiator and a little less under the car, so its a win win for me.