I installed this on
Audi S5

Review
These spark plugs offer a very good performance boost for my engine to deliver the power and torque, along with smoother drives everytime. I don't take my car to the track, but I do drive aggressively(safely too), and these spark plugs are just nice for me! My car now responds much promptly towards my throttle, my steering and had overall provided much better driving experience. I would recommend this for those drivers that drive aggressively and loves great engine response to your gas pedal.

What I like
Improves power and torque, and gives the ability to drive smoothly and comfortably.

What I do not like
Their performance are nearly for track use, hence they are quite expensive.