What do you like best?
RabbitMQ is a great addition to your system.
By leveraging Erlang it provides a high performance, highly concurrent message queue that can enable your applications (written in slower languages - and maybe with worse concurrency models) to scale and serve a higher number of requests.
What do you dislike?
RabbitMQ is a low level tool and you'll need to write some cleverly written library, or tons of configuration to get your stuff done. It would be awesome to have more powerful dead letter functionalities or make the retries flow more approachable.
Recommendations to others considering the product
RabbitMQ is a great tool to handle service communication - you can't go wrong
What business problems are you solving with the product? What benefits have you realized?
I've used RabbitMQ to tackle scalability problems, implement pub-sub flows and overall handle asynchronous communications between services