The Kula is a remarkable piece, and with the Tambaqui DAC installed, I suspect it might represent the pinnacle of current one box solutions.
I have had two of the most popular iterations of the latest Purifi stereo amplifiers paired with SOTA Preamps (A/C and others) in our reference system. The Kula gives up nothing in comparison. I don't believe the Purifi amplifier circuit is better in any way to that of the Kula, with the Kula preamp/amplifier edging out the Purify in terms of authority and dynamics. Detail between the two circuits is equivalent, however, the Kula has been voiced in such a way that the Purifi can only match it when paired with exceptional 5 figure preamps like the best frpm Audionet or Aries Cerat..