So, I've spent a few days with the pickups now, and they're pretty awesome.
When I read a description of the Duncan JB, this is the sound I hear in my head. It has all the good qualities that I read about the JB - warm, articulate, smooth, and (unlike the JB) it actually sounds good to me. To my ears, it sounds a lot like a JB with all the wool removed from the low mids.
In short, they rock.
Welcome to the world of pickups that make sense.