I've owned them and sold them. There is an unavoidable, terrible problem - not everyone loves them. I sold mine to move up the Zu food chain, but otherwise I'd still own 'em and would still be loving them.
I would characterize the Druids as music lover's over audiophile speakers. What they do:
Monster tone, they sound killer on guitar music
Tight bass, down to 40 hz they're very musical. Listen to some acoustic upright and drool
Transient coherence, they speak with "one voice"
Extended at the upper end, well compared with single driver speakers anyway
True SET compatibility
Uncompressed scale with very dynamic music
What they do not do:
Top-shelf air and sparkle in the treble band
Chest kicking in the power zone of the bass, 40 hz - 80 hz
Razor-sharp imaging
I spend a little (as little as possible) time over at Agon. I've seen a lot of folks' reactions to the Druids. Some people really love them and others don't get it. They make perfect, musical sense to me in the same way the vinyl guys are differentiating their plastic from the other in the "Do all CDPs sound the same" thread.
But, they don't check some of the audiophile boxes on "the form". Every speaker is a compromise. I believe the Druids are more different from other speakers than other speakers are from each other. The absense of a crossover in the meat of the music becomes obvious after a while, which may or may not grab you. If it does, you're in for a wild ride. If not, at least you'll know.
I think the reason quite a few pairs have been sold is that Zu is selling a ton of them. I have no idea of the numbers, but I guarantee they're selling a lot more than are coming up for sale. Buying used would be a great way to try them out, or go for the 60-day trial which they have been known to add to at no penalty if you need extra time.
At any rate, whether bought or just auditioned they are a worthy pursuit for audiophiles to at least hear. In your own room or in a worked-out dealership or friend's house, it doesn't matter. They do what matters most to me in music - make BIG tone.