250.8 and XP22.
Demo'd a 250.5 for a short while, though not with a pass pre-amp.
Had the XP12 and 250.8 for a good 2.5 years, but then upgraded to the XP22. XP12 and 250.8 were very good, the XP22 took things to great, and there was a pretty clear difference.
I had the XP12 and 250.8 combo on a pair of DynAudio Contour 60's, Klipsch Epic CF4's (with a few upgrades), Ohm Walsh 5000's, and Salk SS12's (current speakers that I absolutely love). I've had other speakers here on demo's. It's very rare that the XP12 and 250.8 wasn't a nice combo.
Now the XP22 I've heard on the Walsh 5000's, Salk SS12's, Salk Song 3 encore's (friends), martin Logans (Friends), and a couple other demo's.
It's a great combo. Great Midrange, excellent bass, and all the highs (without crazy brightness). I did have a nice Levinson here for a while, and it may have had a shade more detail on the top end, but with a little more harshness in the mids. I felt the Levinson might have been 10% or so tighter in the low end, but with not nearly the oomph.