I have run Koni's for decades & they will outlive the car. The adjustable feature means that as they lose performance due to wear, you can simply adjust them up a little to compensate. They can also be adjusted for cruising or for competition. A little bit dear, but bloody good value.

I used a set on my work Falcons. I used the one set on three diferent cars, swaping them onto each successive new one. I finally let them go when we got a car that they didn't fit. They had near to 300,000k on them & would be ready for a rebuild within another 50,000k.
I will be using the Koni's that i bought about 8 years ago on my KB10.
Chris