I know that the moderators (well, one of them, at least) is groaning to see a post started by me here, but this one is serious.
I have seen a lot of opinions about the Spec clutch. I have only close secondhand experience with it, having helped with a couple of installs. I was far from impressed with it, as 1 out of the 2 installs that I participated in suffered a strange clutch failure before all that long. Maybe it was poor luck, but one strange failure is not reassuring.
I posted a list of links to some of the negative opinions on these clutches, so now I am looking for some unbiased firsthand experiences. I know that most of the people who post about a part do so after it dies a horrible death that often reaks of the expense of collateral damage (i.e. the Cartech).
