Even with pro, I have caught it going off the rails a few times. The most frustrating was when I asked it to do translations, and it decided there were too many to do so it wrote a python script that ran locally and used some terrible library to do literal translations, and some of them were downright offensive and sexual in nature. For translations though, Gemini is the best but you have to have it do a sentence or two at a time. If you provide the context around the text, it really knocks it out of the park