Anybody bought a haldex controller ...s3/tts/etc

[PorkRind]

I'm after people that have bought the haldex controllers to get rid of the understeery mess that haldex creates. I want a more neutral balance and i know i'll never get rearward lead with haldex, but am after some sort of improvements!

What are the options out there for controllers and who has them and were they worth the £?