I am surprised nobody mentioned the Qidi printers. They are the perfect balance between tinkerability and reliability (but see below - QA varies), and have open firmware. They are the only ones that currently compete with Bambu in high-temperature materials. These will outperform PC/Nylon and can also print advanced stuff as PPS, especially on the new Q2.

Now, for their QA - it is not on par with Prusa or Bambu, however, there are a few tips to avoid the pitfalls. 1. If buying the Plus 4, buy the US version of possible. The EU models are older units with a faulty part. 2. Buy from places that offer returns. If the printer is faulty, you can always return it 3. If something breaks, document and send to support. Expect free replacement parts shipped within a week.

By following the above, you will get an extremely capable printer at a fraction of a cost of a Bambu, with offline modes, open source FW a great community and hotend capabilities that are virtually unparalleled and venture into engineering grade machines.

Happy printing :)