I have a Schitt Kara F preamp that replaced the 4x more expensive Holo Audio Serene. The Serene was very good but after a head-2-head with a friend's DIY preamp, the bloom fell off the Serene for me.
I figured the $799 Kara F would be very close to the Serene. It is about 85% as good as the Serene so I sold the Serene.
The Kara F is going into a Schitt Wotan amp (which I really like). I have the Schitt Yggi+ MIB DAC also in the system.
I put my Benchmark HPA4 preamp into the system and loved the sound over the Kara F. As I have said in many posts. You can give me a million $ and for audio and I still use the HPA4 or LA4 preamps.
I even have my office and Livingroom system hooked up to the same HPA4 preamp at the same time. Of course, only one system plays at any time.
The Kara F still gets used, but now only for my RAAL SR1a earphones, via the same Schitt Yggi+ MIB DAC and the Schitt Aegir amp.