Pros
I have built some amazing teams at previous organizations, but OpenAI takes things to a new level with regard to talent bar! The passion that everyone (researchers, engineers, and non-technical team members) exhibits every day to reach our goal of delivering safe Artificial General Intelligence is inspiring. The new office is breathtaking! Compensation is MUCH higher than Glassdoor's limited/fake data. Glad I didn't look there before applying ;-) Collaboration is paramount and everyone at the company is a Slack message or lunch table away. Work/life balance is something that I thought might be lacking with such highly productive, driven teammates, but to a person, weekends and evenings are respected and it feels like everyone knows they do their best work when properly rested and recharged. Knowing you are contributing to such an important mission is really the best "Pro".
Kontras
This is the classic "Con" that is actually a "Pro", but with the talent bar so high, it makes recruiting more challenging. I have had to tell candidates "no" when they receive "yes" from every other interview process. This can sometime be uncomfortable when someone interviews 6 places, receives 5 offers and the place they really want to work says "not quite".