Cons: you might be sick for a day. (Had very bad reactions to the shots and this one lasted 1 day - but I caught something else before/after...)
Pros: seems to help against Omikron. And given the speed at which it spreads you don't have time to wait for updated shots or alike.
JJ was particularly bad in not catching it, and even worse after 6 months. Get a booster or have a close to 100% chance to catch Omikron.
Official communication is often skewed by availability. E.g. Germany didn't order enough BionTech but got plenty of Moderna so they announced that Moderna is way better. Just check the numbers and forget about anything else in the news. Numbers are like a weather forecast. Read it, prepare, put it aside.