I tested o3 on a medical issue I've had that 50+ doctors couldn't diagnose over the span of 6-7 years, ended up figuring it out through sheer luck. With my first prompt, it gave a list of probabilities, with the correct answer being listed as the third most likely. It also suggested correct tests to run for every option. I trust it way more than I trust human doctors who were confidently wrong about me for years.