I am currently a contributor to a system that uses CQRS + ES. We are a fintech company and the positives we have adopting it outweighs the negatives.

We use Lagom framework to implement CQRS+ES over Akka Actors and related technologies. There's enough guardrails/guides within the Lagom framework and documentations that it's hard to screw up too badly. And IMO I think the different pieces fit together very nicely!

Overall the tradeoffs in system complexity vs scalability isn't too shabby.