Coilovers - Bilstein B14 or KW Street Comfort

I'm currently looking into fitting a set of coilovers to the ol' girl.. I like the look (and cheapness!) of just fitting a set of H&R springs, but the reality is that it's false economy just doing springs on standard dampers that have got 80k miles on them already. So, ruling out cheap rubbish like VMaxx etc.. does anyone have any experience with the two kits above?

I'm looking for the 'Holy Grail' I suppose of lowering the car around 40mm, whilst still keeping most, if not all, of the current ride comfort.. just without the huge amounts of wallow.
I remember having Bilstein years ago on an old Seat Ibiza, which was a pretty harsh ride and used to get rear tyre rub when fully laden.. but that was their old Streetline kit, not coilovers.

Money wise they're about the same price fitted and aligned etc.. so, really need to test drive the two, but that'll never happen.
So, has anyone on here got either on their Superb (estate ideally)?