I had a look at the rear springs of my recently acquired Zed. It has had at least one spring replaced but the other is clearly much older. The general opinion on the Forum is that they should be replaced in pairs. The build sheet for the car says that it has the S704A option which is described as "M Sports suspension". What exactly does this mean and does it affect what rear springs I should get? I was thinking of getting a pair of Suplex springs - is this OK or should I be looking at something else because of the S704A option? :?