"Reference" Preamps

Seems like every time I turn my head there's a new "reference" preamp available. Heck, in this month's stereophile there are TWO that are better than anything else out there. Seems like their reviewers don't talk to one another.

Problem is that no one in the press ever wants to COMPARE sonics anymore, but they're oh so quick to throw superlatives around, and gush over dozens of subjective attributes.

I want to upgrade my ARC LS25mk2 preamp and would like to know where to spend my time. These are all $10kish msrp preamps that would hopefully fall into the "last preamp I'll ever want to own" category.

Audio Research Reference 3
Ayre K1xe
BAT VK-51SE
EAR 912
Mark Levinson 326

Didn't make my list:

Conrad-Johnson ACT2 (no balanced outs)
Hovland HP1000 (no balanced outs)
Lamm Reference 2 (no remote, separate volume controls)

Would someone care to start offering comparative opinions on these? What other preamps should I add to this list?

Thanks!