I saw some recommendations for Line Magnetic amps here. I don't know how the customer support in the United States is, but my customer journey with the Line Magnetic LM-503PA Mono Vacuum Tube Amps in Vienna is terrible.
Spoiler: Would I recommend buying a Line Magnetic product? Not when you are in Germany or Austria.
In the Summer of 2021, I spent 10k on a pair of Line Magnetic LM-503PA mono vacuum tube amps. This was by far my worst decision in 40 years of buying hi-fi gear.
So far, I have enjoyed listening with the amps for 11 months. But for 5 months, I couldn't enjoy listening with the amps because of defects and ridiculous customer support. As I'm writing this, my Line Magnetic LM-503PA is defective at the distributor for repair for more than four weeks, and Line Magnetic has not even sent the missing spare parts from China to Germany yet. But this is just the tip of the iceberg of my terrible customer experience with a Line Magnetic product.
This is why I wrote a customer report about my journey with the Line Magnetic LM-503PA mono vacuum tube amp. The report is about many customer-unfriendly emails, a dealer who doesn't answers emails at all, the European Line Magnetic distributor holding my amp hostage, and Line Magnetic in China refusing to answer my questions.