microservice communication sync vs async

Hey everyone, I've been thinking a lot about how we should manage communication between our microservices. For situations where two services need to talk directly, and one needs an immediate reply, synchronous methods like REST calls seem pretty obvious. But when do you think it's a better idea to go with asynchronous communication, maybe using a message queue, even if the service getting the message doesn't need it right away? I'm trying to weigh the pros and cons for our setup.