Is gpt4 as good in non-English uses? It's not clear to me that it would be particularly important or advantageous, but does Mistral being based in Europe and polyglot first make it interesting vs. gpt4 in some dimension?
Especially in terms of open models Mistral's are the most multilingual but outside a few handpicked ones the level of proficiency is just too poor for any real usage.
If you want to be able to give basic commands and have the model reason about the logic behind your commands, gpt 4 is still the best, even in minority languages.