Yeah try something out and see if it works for you.
Feedback I’ve had from customers using ELK have been that it requires a fair amount of dev/customisation to get it to do what you want. It’s there as a platform, but you then have to develop the content yourself.
Now this was before ELK came out with their SIEM side to the product so this may have changed.
They also said that over the period they’ve had it, it’s cost them more than buying a ‘commercial’ SIEM tool once they’ve bought the required hardware, and paid for all the consultancy they needed (that was another gripe they had, availability of skilled resource).
They could make this comparison as they ran both ELK and another commercial SIEM tool within their company so could easily see the differences.
On the flip side, as they had to develop their use cases and content themselves they actually did things ‘right’ in properly threat modelling things to create content that was relevant to them, rather than just take off the shelf content and never touch it.
All of that is related to using the products as a SIEM, so not just log collection and searching/reporting.
Still not had a good play with ELK myself yet but keep meaning to