Anyone compared BAT Rex vs. Atmasphere MP-1?

Obviously, there is a big price difference between the two(not as big used). But, these two are likely to be in the top of the true balanced, fully differential, reference preamps available.

I'm mostly interested in the sonic differences anyone would have noticed switching between the two in their own system.
Maril555, my MP-1 is a modded MkII that replaced a BAT VK5i and VKP10. The main thing about Atma is the sense of wide open bandwidth and agility, as compared to the mellower & prettier sound of BAT. However at CES BAT REX components were fast on their feet, effortless, yet a bit fuller in embodiment than I hear at home. Of several exhibits this was the only one that had convincing synergy with Shashas. In other contexts at THE Show I heard MP-1 Mk III sound remarkable with Classic Audio Reproduction field coils and VPMS. It's a close horse race.
I heard MP-1 in the same room at THE Show with CAR speakers, and liked the room very much.
i agree with dgarretson that mp-1 are moreso than most any at being wide open, add they are great at chameleon. I've had loads of fun rolling tubes and finding what I like for certain disks to help "flesh out" or even "thin out" the musical presentation, at my discretion. great unit.
Ralph- I just saw (for the first time) your MP-1, but with a stunning brushed alum. finish. IF you had that available 2 years ago, I would be a proud owner. Well, hopefully my next preamp. Impedance wise, is the MP-1 a good match for Burmester 911 MK3?
Talk2me, There is no power amp made that has an input impedance too low for the MP-1 (it can drive 32-ohm headphones directly from the same outputs that drive the power amps). The Burmester is completely balanced, so no worries.