If you are concerned about the comfort of the ride of the vehicle, then I would be careful about selecting anything other than the OEM equipment. These Volvo suspensions are not very forgiving on this matter.

I've used Bilstein HD's in an early body 960 and it was a mistake. Great shock, but bad match for the Volvo suspension design. Only the engineers are going to be able to make the best call on achieving the optimal balance of comfort and handling. If you change the damping of the shock, then you move off on your own and it's hard to even know how far you're moving off the original design.

My philosophy on shocks and suspension rubbers is that unless you're into racing and thus insistent on doing your own thing, stick with the OEM stuff because the annoyance of degrading the riding comfort factor is something you will have to live with for some time. I also try to change the rubbers if at all possible. The change in the damping qualities of rubber is a thing that is almost impossible to gauge be inspection, and even if you bought a new car and put only 3000 miles on it in 15 years, the suspension rubber would STILL go bad from age.

Money, money, money . . .