Here is a 2-year follow-up on my cluch review:
The clutch behaved flawlessly over this time. It never ever slipped. But I did not launch it with drag radials more than 10-15 times. However, I did abuse it while daily driving it quite a lot.
Today, 2 years later, I decided to replace my Sachs Performance 4-puck setup with a Sachs Performance organic setup with reinforced clutch cover. Why ? The main reason is that I gave up participating to drag racing events due to increasing costs of bringing drag radials from the US into my EU country (basically the price more than doubles), etc. The other main reason is that the clutch became a little grabbier than I would like and it's not ideal in the stop-and-go traffic that I am facing everyday to work. Basically it became tiring to drive, the window of slipping the clutch is very narrow and you always have to take care of this while driving. An (intermittent but mostly present) screeching sound when taking off (only in 1st gear) was also present, sometimes people look at your car and you think that they are saying "dude, your car is broken"
So of course, after two years of stop-and-go driving, I expected a puck cluch to be worn, and the flywheel to be shot due to the shocks, as I read on other forums.
Well, guess what: everything was in "like-new" condition (pictures below). Not the slightest heat mark on the flywheel, the clutch disc was worn 1/2mm max. and the clutch plate looked like new. What suprised me the most is that the flywheel had no play at all compared to the new one ! I guess LUK improved their flywheels recently, my previous two flywheels had quite a lot of play when removed. I almost felt sorry for the money paid to replace it - but after I drove off from the car shop the ease of driving with the new organic clutch made the switch worth it for me. However, I am not sure how much this new setup will last until slipping. If if does slip over time, I will probably replace it with the puck setup again.
So basically, if you want a racing clutch that can be driven daily without getting worn, and don't mind the added grabby-ness over an organic setup, this clutch is a very good option.
Pictures of the removed clutch parts below.