BAT VK-200, Plinius SA100 MK3, or Levinson 27.5?

I am pretty sure the Plinius is not truly balanced, so with that pre amp I would look into the other two. I am not familar with the levinson but that model sounds like it hasn't been made in a while. Come to think of it all of those choices I believe are no longer being produced. I have had great luck with BAT, in particular if you have a good truly balanced preamp, you would get better results using a truly balanced amp.

I owned the Levinson 27.5 and it is an outstanding amp.
Dynamic, spacious, excellent imaging, no harshness.
I sold it only to buy a Levinson 335 because I needed
more power. Many consider the 27.5 one of the best amps
ever made by Madrigal.

The BAT is slightly dark-sounding, hard to describe but not as airy or sparkling as most amps. A great choice if your speakers or upstream components sound a little too bright. The ML 27.5 is a great amp and thought by many to be superior to their newer stuff. ML's seem to err a little to the "refined" side of things to my ears, almost too smooth. But again, many people love them for just that reason. YMMV.