https://spun.io/2019/10/10/aws-elasticsearch-a-fundamentally...
https://code972.com/blog/2017/12/why-you-shouldnt-use-aws-el...
Make darn well sure you aren't using any unsupported operations.
In their favor, if I were to revisit them I could use it now; however in the past they didn't support templates and a few other things which turned out to be major blockers.
More details here - https://www.akshaysurve.com/2018/01/what-we-like-about-amazo...
If you want to get it set up and running most of the way without tuning a bunch of stuff it’s pretty good.
It also has significant cost overhead compared to self-managed and limited instance types.
My team now is working on migrating a 2.3 cluster from AWS ES to a 7.8 self-managed cluster (probably 7.9 now I guess). We do lots of indexing throughout the day and the i3 instances available are pretty weak, just switching to r5d/r6gd instances greatly reduced our indexing and search latency