When should you use gRPC instead of REST for services talking to each other?

Hey everyone, I'm trying to pick the right way for our new internal microservices to talk to each other. We usually go with REST APIs and JSON, which works, but I keep hearing good things about gRPC, especially for services talking directly. So, where does gRPC truly stand out, besides just being quicker? I'm wondering about stuff like how it handles schema changes, what tools are out there, and what it's like for developers. What have you all found when bringing gRPC into your own internal systems? And when does setting up all those Protobuf definitions actually make sense?