Perplexity seems to do a pretty good job, whereas Copilot makes stuff up all the time.
All LLMs I’ve tested had a tendency to agree with my delusions and misconceptions, so you have to be very cautious not to ask loaded questions. If you start misleading the LLM, it will go with the flow and give you a wrong answer.
Copilot and chatGPT prefer to avoid PR disasters, but Mistral has no issues with sensitive topics. Mistral doesn’t really seem to have much opinions about anything so you can dive into any topic you like. The other LLMs do have clear opinions and lines they won’t cross.