I recently moved on to a new company, but my prior company had a pretty large scale Elasticache Redis deployment in production (over 50 large clusters in us-east-1), and were in the middle of a complete migration to Valkey due cost savings, improved performance, and reduction in memory usage.

We've already completed migrating several large production clusters and I can confidently say that the migration had been pretty smooth and seamless.

Valkey is certainly production ready (at least on AWS it is). The team is looking forward to expedite and complete the migration