Just installed it today. Install was a cinch except that the short clip was a pain to get to. Very limited ability to really get on it after the install, but I could tell immediately that she was pushing a lot more from the rear. I gave it a few good 0-60 launches and it noticeably launched from the rear more and got off the line more quickly, transforming the launch of the car compared to stock launches (which had seemed to bog down at best). I'll start a proper thread and review when I get back from the mountains, but I'm already happy with it and can't wait to see how different twisty bits are with this upgrade.
Everyone, this upgrade in my opinion makes the car drive more neutral with more of a rear push coming out of turns and from a standstill. Easily one of my favorite upgrades I've done to the car, what a difference!!
Install was pretty straight forward, mine was spilling gear oil when we removed the old unit so we quickly had to swap the new controller in. Tighten two bolts, plug in the two connectors and good to go!
I gave my HPA Haldex controller a workout last weekend. Even the tightest and fastest corners are no drama. It makes me a bit afraid to find out where the limits are. Even when I drive aggressively - for me - the system makes me look good!