I'm sure I'd never spend the $$$ for the PPG nor the Griffin, so my questions are merely idle curiosity-
I can't tell for sure but the Griffin appears to use Hypoid ring/pinion gears. If so, I would wonder why an all-newly-configured transaxle wouldn't employ [more efficient] bevel gears- either spiral or straight-tooth. [Historical note: Hypoid gearsets were originally introduced to allow lower floors in passenger cars in the nineteen-thirties]. The market for this transaxle is performance-oriented, not for passenger car use.