Speaking from experience with both OEM and ziza fog light housings; both work, and the lenses are pretty much the same on both, fitment for both in the bumper is identical.
What differentiates them is their longevity. The metal and plastic on the OEM housings will outlast the knock offs hands down. The adjustment screw on the knock offs will always rust and seize, the plastics will break and crack, and the finish will peel.
OEM housings will remain relatively fresh and functional for the life of their service.
You won't regret going OEM, especially at that discount.