Elastic Search River and Rabbit MQ integration

Hello,

We are investigating to integrate Rabbit MQ with River.

Our requirement is to index the data which is being pushed to the Rabbit
MQ. River can be configured to listen for topic/routing key.

I had seen some post that use bulk API/manual indexing instead of river. is
there any disadvantage using River?

I will be keep posting questions...it's just a kick start!

Thanks
Prab