I had the Mulberry parts installed for a while in my 4/4 Sport ... I could not tell any difference.
What annoyed me was the fact that there is not enough clearence and the (stock) tires rub on the stay on full lock -> removed.
Wolfgang
I've had exactly the same experience on my 4/4.
With hindsight I don't think they are that necessary on the 4/4 with 165 tyres because the maximum braking force is probably not enough to twist the crosshead.
On cars with bigger brakes and wider tyres the stays probably do make a difference but I'm doubtful on the 4/4.
I noticed the reduced lock and have been deciding whether to put up with it but yesterday while I was fitting some braided brake hoses I noticed the tyres have been rubbing heavily on the stays so I think they will have to come off.
I don't know why they would rub on the 4/4 and not other models or maybe people are just putting up with it.
Has anyone ever had an MOT problem because of the rubbing.