As far as I know, Proton uses local and foreign supplier as their vendor, I think the local one is more like cost-saving since these are vendors that caused a lot of problem for Proton in terms of quality such as EPMB (for IAFM module), Sapura (Saga drumbrake), other foreign vendors (Bosch, Punch, Saint-Gobain, DK-Schweizer, Sanden) are doing ok for Proton. When there's a problem, Proton always kena even though the vendor caused it in the first place...