my quad CF diffuser from JW-Tuning is right now being installed and the are some "huge" gaps on the left and much more on the right. Something about 4-5mm.
i am a bit disapointed of the product's fitment
i previously had a single CF diffuser from adamaster, i did much better fit (also they carbon-ed a OEM diffuser, as i saw). sure it was 10x heavier that the JW-Tuning's quad CF diffuser, but it did fit right on the cornes, borners, and so on.
we will see once the car is down the lift ...