What! Nobody got an opinion - that's not the Pelican forum members I know.
Having done a bit more research, it would seem if I want to retain PASM, Bilstein is the only game in town. However I will probably go for the slightly more expensive B6 range rather than the standard B4. Bilstein also do a B8 and a Damptronic range but it seems to me that those are more for track day cars and involve lowering the suspension. I have a 1/2 mile long very bumpy drive in the UK, on which I already tend to clip the rubber spoiler lip, so lowering is out.