FWIW, during late-summer '10 I demo'd many floorstanders, up to £2600 RRP, incl Spendor, ATC, PMC, ProAc, B&W, Vienna, MA and Amphion.
All were demo'd with an Arcam A38 - recipient of lukewarm 3-star from WHF? but, curiously, enthusiastic 5-star reviews from 'other leading publications' in the UK and US. (BTW, the A38 pumps out 100W.) And IME the A38 responds very well to bi-amp'ing.
To my ears, when hooked up to the A38, all the speakers I demo'd sounded either 'dry', limp or hideously unbalanced (ie, top-end brightness).
However, ProAc's D18 was all-round chuffing gorgeous: instruments sounded realsitic/musical and exciting; heaps of detail/separation/imaging/soundstage; impressive bass in mid-range and low-end. And the D18s look cool :dance:
Try a D18 + A38 home-demo - there's now't to lose? A38's RRP is £1500 or can be had ex-demo/display for approx £900 or £700-800 2nd-hand on eBay etc.
IMVHO, the D18 is so good it's almost worth building a system around it.